Fix 3000 errors

Content.Client/AI/ClientAiDebugSystem.cs

@@ -18,7 +18,7 @@ namespace Content.Client.AI
         [Dependency] private readonly IEyeManager _eyeManager = default!;
 
         private AiDebugMode _tooltips = AiDebugMode.None;
-        private readonly Dictionary<IEntity, PanelContainer> _aiBoxes = new();
+        private readonly Dictionary<EntityUid, PanelContainer> _aiBoxes = new();
 
         public override void Update(float frameTime)
         {
@@ -37,7 +37,7 @@ namespace Content.Client.AI
                 return;
             }
 
-            var deletedEntities = new List<IEntity>(0);
+            var deletedEntities = new List<EntityUid>(0);
             foreach (var (entity, panel) in _aiBoxes)
             {
                 if ((!IoCManager.Resolve<IEntityManager>().EntityExists(entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted)
@@ -78,8 +78,7 @@ namespace Content.Client.AI
             if ((_tooltips & AiDebugMode.Thonk) != 0)
             {
                 // I guess if it's out of range we don't know about it?
-                var entityManager = IoCManager.Resolve<IEntityManager>();
+                var entity = message.EntityUid;
-                var entity = entityManager.GetEntity(message.EntityUid);
                 TryCreatePanel(entity);
 
                 // Probably shouldn't access by index but it's a debugging tool so eh
@@ -95,8 +94,7 @@ namespace Content.Client.AI
         {
             if ((_tooltips & AiDebugMode.Paths) != 0)
             {
-                var entityManager = IoCManager.Resolve<IEntityManager>();
+                var entity = message.EntityUid;
-                var entity = entityManager.GetEntity(message.EntityUid);
                 TryCreatePanel(entity);
 
                 var label = (Label) _aiBoxes[entity].GetChild(0).GetChild(1);
@@ -110,8 +108,7 @@ namespace Content.Client.AI
         {
             if ((_tooltips & AiDebugMode.Paths) != 0)
             {
-                var entityManager = IoCManager.Resolve<IEntityManager>();
+                var entity = message.EntityUid;
-                var entity = entityManager.GetEntity(message.EntityUid);
                 TryCreatePanel(entity);
 
                 var label = (Label) _aiBoxes[entity].GetChild(0).GetChild(1);
@@ -154,7 +151,7 @@ namespace Content.Client.AI
             }
         }
 
-        private bool TryCreatePanel(IEntity entity)
+        private bool TryCreatePanel(EntityUid entity)
         {
             if (!_aiBoxes.ContainsKey(entity))
             {

Content.Client/AI/ClientPathfindingDebugSystem.cs

@@ -287,7 +287,7 @@ namespace Content.Client.AI
         private void DrawCachedRegions(DrawingHandleScreen screenHandle, Box2 viewport)
         {
             var attachedEntity = _playerManager.LocalPlayer?.ControlledEntity;
-            if (attachedEntity == null || !CachedRegions.TryGetValue(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity).GridID, out var entityRegions))
+            if (attachedEntity == default || !CachedRegions.TryGetValue(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity.Value).GridID, out var entityRegions))
             {
                 return;
             }
@@ -305,7 +305,7 @@ namespace Content.Client.AI
                         screenTile.X + 15.0f,
                         screenTile.Y + 15.0f);
 
-                    screenHandle.DrawRect(box, _cachedRegionColors[IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity).GridID][region]);
+                    screenHandle.DrawRect(box, _cachedRegionColors[IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity.Value).GridID][region]);
                 }
             }
         }
@@ -336,7 +336,7 @@ namespace Content.Client.AI
         private void DrawRegions(DrawingHandleScreen screenHandle, Box2 viewport)
         {
             var attachedEntity = _playerManager.LocalPlayer?.ControlledEntity;
-            if (attachedEntity == null || !Regions.TryGetValue(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity).GridID, out var entityRegions))
+            if (attachedEntity == default || !Regions.TryGetValue(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity.Value).GridID, out var entityRegions))
             {
                 return;
             }
@@ -356,7 +356,7 @@ namespace Content.Client.AI
                             screenTile.X + 15.0f,
                             screenTile.Y + 15.0f);
 
-                        screenHandle.DrawRect(box, _regionColors[IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity).GridID][chunk][region]);
+                        screenHandle.DrawRect(box, _regionColors[IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(attachedEntity.Value).GridID][chunk][region]);
                     }
                 }
             }

Content.Client/AME/Visualizers/AMEControllerVisualizer.cs

@@ -9,7 +9,7 @@ namespace Content.Client.AME.Visualizers
     [UsedImplicitly]
     public class AMEControllerVisualizer : AppearanceVisualizer
     {
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
             var sprite = IoCManager.Resolve<IEntityManager>().GetComponent<ISpriteComponent>(entity);

Content.Client/AME/Visualizers/AMEVisualizer.cs

@@ -9,7 +9,7 @@ namespace Content.Client.AME.Visualizers
     [UsedImplicitly]
     public class AMEVisualizer : AppearanceVisualizer
     {
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
             var sprite = IoCManager.Resolve<IEntityManager>().GetComponent<ISpriteComponent>(entity);

Content.Client/Actions/ActionsSystem.cs

@@ -84,7 +84,7 @@ namespace Content.Client.Actions
             return new((in PointerInputCmdHandler.PointerInputCmdArgs args) =>
                 {
                     var playerEntity = _playerManager.LocalPlayer?.ControlledEntity;
-                    if (playerEntity == null ||
+                    if (playerEntity == default ||
                         !EntityManager.TryGetComponent<ClientActionsComponent?>(playerEntity.Value, out var actionsComponent)) return false;
 
                     actionsComponent.HandleHotbarKeybind(slot, args);
@@ -98,7 +98,7 @@ namespace Content.Client.Actions
             return new((in PointerInputCmdHandler.PointerInputCmdArgs args) =>
                 {
                     var playerEntity = _playerManager.LocalPlayer?.ControlledEntity;
-                    if (playerEntity == null ||
+                    if (playerEntity == default ||
                         !EntityManager.TryGetComponent<ClientActionsComponent?>(playerEntity.Value, out var actionsComponent)) return false;
 
                     actionsComponent.HandleChangeHotbarKeybind(hotbar, args);
@@ -110,7 +110,7 @@ namespace Content.Client.Actions
         private bool TargetingOnUse(in PointerInputCmdHandler.PointerInputCmdArgs args)
         {
             var playerEntity = _playerManager.LocalPlayer?.ControlledEntity;
-            if (playerEntity == null ||
+            if (playerEntity == default ||
                 !EntityManager.TryGetComponent<ClientActionsComponent?>(playerEntity.Value, out var actionsComponent)) return false;
 
             return actionsComponent.TargetingOnUse(args);
@@ -119,7 +119,7 @@ namespace Content.Client.Actions
         private void ToggleActionsMenu()
         {
             var playerEntity = _playerManager.LocalPlayer?.ControlledEntity;
-            if (playerEntity == null ||
+            if (playerEntity == default ||
                 !EntityManager.TryGetComponent<ClientActionsComponent?>(playerEntity.Value, out var actionsComponent)) return;
 
             actionsComponent.ToggleActionsMenu();

Content.Client/Actions/ClientActionsComponent.cs

@@ -1,7 +1,5 @@
 using Content.Client.Actions.Assignments;
 using Content.Client.Actions.UI;
-using Content.Client.Hands;
-using Content.Client.Inventory;
 using Content.Client.Items.Managers;
 using Content.Shared.Actions.Components;
 using Content.Shared.Actions.Prototypes;
@@ -226,7 +224,7 @@ namespace Content.Client.Actions
         /// Highlights the item slot (inventory or hand) that contains this item
         /// </summary>
         /// <param name="item"></param>
-        public void HighlightItemSlot(IEntity item)
+        public void HighlightItemSlot(EntityUid item)
         {
             StopHighlightingItemSlots();
 
@@ -236,7 +234,7 @@ namespace Content.Client.Actions
 
         /// <summary>
         /// Stops highlighting any item slots we are currently highlighting.
-        /// </summary>
+        /// </summary>H
         public void StopHighlightingItemSlots()
         {
             if (_highlightedEntity == default)

Content.Client/Actions/UI/ActionSlot.cs

@@ -62,7 +62,7 @@ namespace Content.Client.Actions.UI
         /// Item the action is provided by, only valid if Action is an ItemActionPrototype. May be null
         /// if the item action is not yet tied to an item.
         /// </summary>
-        public IEntity? Item { get; private set; }
+        public EntityUid Item { get; private set; }
 
         /// <summary>
         /// Whether the action in this slot should be shown as toggled on. Separate from Depressed.
@@ -231,7 +231,7 @@ namespace Content.Client.Actions.UI
             {
                 ActionPrototype actionPrototype => new ActionAttempt(actionPrototype),
                 ItemActionPrototype itemActionPrototype =>
-                    (Item != null && IoCManager.Resolve<IEntityManager>().TryGetComponent<ItemActionsComponent?>(Item, out var itemActions)) ?
+                    (Item != default && IoCManager.Resolve<IEntityManager>().TryGetComponent<ItemActionsComponent?>(Item, out var itemActions)) ?
                         new ItemActionAttempt(itemActionPrototype, Item, itemActions) : null,
                 _ => null
             };
@@ -245,7 +245,7 @@ namespace Content.Client.Actions.UI
             _beingHovered = true;
             DrawModeChanged();
             if (Action is not ItemActionPrototype) return;
-            if (Item == null) return;
+            if (Item == default) return;
             _actionsComponent.HighlightItemSlot(Item);
         }
 
@@ -376,7 +376,7 @@ namespace Content.Client.Actions.UI
             if (Action != null && Action == action) return;
 
             Action = action;
-            Item = null;
+            Item = default;
             _depressed = false;
             ToggledOn = false;
             ActionEnabled = actionEnabled;
@@ -395,10 +395,10 @@ namespace Content.Client.Actions.UI
         public void Assign(ItemActionPrototype action)
         {
             // already assigned
-            if (Action != null && Action == action && Item == null) return;
+            if (Action != null && Action == action && Item == default) return;
 
             Action = action;
-            Item = null;
+            Item = default;
             _depressed = false;
             ToggledOn = false;
             ActionEnabled = false;
@@ -415,7 +415,7 @@ namespace Content.Client.Actions.UI
         /// <param name="action">action to assign</param>
         /// <param name="item">item the action is provided by</param>
         /// <param name="actionEnabled">whether action should initially appear enable or disabled</param>
-        public void Assign(ItemActionPrototype action, IEntity item, bool actionEnabled)
+        public void Assign(ItemActionPrototype action, EntityUid item, bool actionEnabled)
         {
             // already assigned
             if (Action != null && Action == action && Item == item) return;
@@ -439,7 +439,7 @@ namespace Content.Client.Actions.UI
         {
             if (!HasAssignment) return;
             Action = null;
-            Item = null;
+            Item = default;
             ToggledOn = false;
             _depressed = false;
             Cooldown = null;
@@ -502,7 +502,7 @@ namespace Content.Client.Actions.UI
                 SetActionIcon(Action.Icon.Frame0());
             }
 
-            if (Item != null)
+            if (Item != default)
             {
                 SetItemIcon(IoCManager.Resolve<IEntityManager>().TryGetComponent<ISpriteComponent?>(Item, out var spriteComponent) ? spriteComponent : null);
             }

Content.Client/Actions/UI/ActionsUI.cs

@@ -378,10 +378,10 @@ namespace Content.Client.Actions.UI
         private void UpdateActionSlot(EntityUid item, ItemActionType itemActionType, ActionSlot actionSlot,
             ActionAssignment? assignedActionType)
         {
-            if (!_entityManager.TryGetEntity(item, out var itemEntity)) return;
+            if (!_entityManager.EntityExists(item)) return;
             if (_actionManager.TryGet(itemActionType, out var action))
             {
-                actionSlot.Assign(action, itemEntity, true);
+                actionSlot.Assign(action, item, true);
             }
             else
             {
@@ -420,7 +420,7 @@ namespace Content.Client.Actions.UI
 
                 // if we are targeting with an action now on cooldown, stop targeting if we should
                 if (SelectingTargetFor?.Action != null && SelectingTargetFor.Action == action &&
-                    SelectingTargetFor.Item == itemEntity &&
+                    SelectingTargetFor.Item == item &&
                     actionState.IsOnCooldown(_gameTiming) && action.DeselectOnCooldown)
                 {
                     StopTargeting();

Content.Client/Administration/AdminNameOverlay.cs

@@ -1,6 +1,4 @@
-using System.Collections.Generic;
+using Robust.Client.Graphics;
-using Content.Shared.Administration.Events;
-using Robust.Client.Graphics;
 using Robust.Client.ResourceManagement;
 using Robust.Shared.Enums;
 using Robust.Shared.GameObjects;
@@ -36,7 +34,8 @@ namespace Content.Client.Administration
             foreach (var playerInfo in _system.PlayerList)
             {
                 // Otherwise the entity can not exist yet
-                if (!_entityManager.TryGetEntity(playerInfo.EntityUid, out var entity))
+                var entity = playerInfo.EntityUid;
+                if (!_entityManager.EntityExists(entity))
                 {
                     continue;
                 }

Content.Client/Administration/UI/ManageSolutions/EditSolutionsWindow.xaml.cs

@@ -1,3 +1,5 @@
+using System;
+using System.Collections.Generic;
 using Content.Shared.Chemistry.Components;
 using Robust.Client.AutoGenerated;
 using Robust.Client.Console;
@@ -7,8 +9,6 @@ using Robust.Client.UserInterface.XAML;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Localization;
-using System;
-using System.Collections.Generic;
 
 namespace Content.Client.Administration.UI.ManageSolutions
 {
@@ -46,8 +46,8 @@ namespace Content.Client.Administration.UI.ManageSolutions
         {
             _target = target;
 
-            var targetName = _entityManager.TryGetEntity(target, out var entity)
+            var targetName = _entityManager.EntityExists(target)
-                ? IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityName
+                ? IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(target).EntityName
                 : string.Empty;
 
             Title = Loc.GetString("admin-solutions-window-title", ("targetName", targetName));

Content.Client/Administration/UI/Tabs/AtmosTab/AddAtmosWindow.xaml.cs

@@ -23,8 +23,8 @@ namespace Content.Client.Administration.UI.Tabs.AtmosTab
             _data = IoCManager.Resolve<IMapManager>().GetAllGrids().Where(g => (int) g.Index != 0);
             foreach (var grid in _data)
             {
-                IEntity? tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
+                var tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
-                var playerGrid = (tempQualifier != null ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier) : null).GridID;
+                var playerGrid = (tempQualifier != default ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier.Value) : null)?.GridID;
                 GridOptions.AddItem($"{grid.Index} {(playerGrid == grid.Index ? " (Current)" : "")}");
             }
 

Content.Client/Administration/UI/Tabs/AtmosTab/AddGasWindow.xaml.cs

@@ -1,7 +1,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using Content.Client.Atmos.EntitySystems;
-using Content.Shared.Atmos;
 using Content.Shared.Atmos.Prototypes;
 using JetBrains.Annotations;
 using Robust.Client.AutoGenerated;
@@ -28,8 +27,8 @@ namespace Content.Client.Administration.UI.Tabs.AtmosTab
             _gridData = IoCManager.Resolve<IMapManager>().GetAllGrids().Where(g => (int) g.Index != 0);
             foreach (var grid in _gridData)
             {
-                IEntity? tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
+                var tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
-                var playerGrid = (tempQualifier != null ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier) : null).GridID;
+                var playerGrid = (tempQualifier != default ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier.Value) : null)?.GridID;
                 GridOptions.AddItem($"{grid.Index} {(playerGrid == grid.Index ? " (Current)" : "")}");
             }
 

Content.Client/Administration/UI/Tabs/AtmosTab/FillGasWindow.xaml.cs

@@ -1,7 +1,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using Content.Client.Atmos.EntitySystems;
-using Content.Shared.Atmos;
 using Content.Shared.Atmos.Prototypes;
 using JetBrains.Annotations;
 using Robust.Client.AutoGenerated;
@@ -28,8 +27,8 @@ namespace Content.Client.Administration.UI.Tabs.AtmosTab
             _gridData = IoCManager.Resolve<IMapManager>().GetAllGrids().Where(g => (int) g.Index != 0);
             foreach (var grid in _gridData)
             {
-                IEntity? tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
+                var tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
-                var playerGrid = (tempQualifier != null ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier) : null).GridID;
+                var playerGrid = (tempQualifier != default ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier.Value) : null)?.GridID;
                 GridOptions.AddItem($"{grid.Index} {(playerGrid == grid.Index ? " (Current)" : "")}");
             }
 

Content.Client/Administration/UI/Tabs/AtmosTab/SetTemperatureWindow.xaml.cs

@@ -23,8 +23,8 @@ namespace Content.Client.Administration.UI.Tabs.AtmosTab
             _data = IoCManager.Resolve<IMapManager>().GetAllGrids().Where(g => (int) g.Index != 0);
             foreach (var grid in _data)
             {
-                IEntity? tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
+                var tempQualifier = IoCManager.Resolve<IPlayerManager>().LocalPlayer?.ControlledEntity;
-                var playerGrid = (tempQualifier != null ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier) : null).GridID;
+                var playerGrid = (tempQualifier != default ? IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(tempQualifier.Value) : null)?.GridID;
                 GridOptions.AddItem($"{grid.Index} {(playerGrid == grid.Index ? " (Current)" : "")}");
             }
 

Content.Client/Animations/ReusableAnimations.cs

@@ -12,7 +12,7 @@ namespace Content.Client.Animations
 {
     public static class ReusableAnimations
     {
-        public static void AnimateEntityPickup(IEntity entity, EntityCoordinates initialPosition, Vector2 finalPosition)
+        public static void AnimateEntityPickup(EntityUid entity, EntityCoordinates initialPosition, Vector2 finalPosition)
         {
             var animatableClone = IoCManager.Resolve<IEntityManager>().SpawnEntity("clientsideclone", initialPosition);
             string val = IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityName;
@@ -28,7 +28,7 @@ namespace Content.Client.Animations
 
             var animations = IoCManager.Resolve<IEntityManager>().GetComponent<AnimationPlayerComponent>(animatableClone);
             animations.AnimationCompleted += (_) => {
-                IoCManager.Resolve<IEntityManager>().DeleteEntity((EntityUid) animatableClone);
+                IoCManager.Resolve<IEntityManager>().DeleteEntity(animatableClone);
             };
 
             animations.Play(new Animation

Content.Client/Atmos/Visualizers/AtmosPlaqueVisualizer.cs

@@ -13,7 +13,7 @@ namespace Content.Client.Atmos.Visualizers
         [DataField("layer")]
         private int Layer { get; }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Atmos/Visualizers/EnabledAtmosDeviceVisualizer.cs

@@ -2,6 +2,7 @@ using System;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Atmos.Visualizers
@@ -20,7 +21,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
                 return;
 
             if(component.TryGetData(DataKey, out bool enabled) && sprite.LayerMapTryGet(LayerMap, out var layer))

Content.Client/Atmos/Visualizers/FireVisualizer.cs

@@ -1,5 +1,4 @@
 using Content.Shared.Atmos;
-using Content.Shared.Atmos.Components;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
@@ -23,7 +22,7 @@ namespace Content.Client.Atmos.Visualizers
         [DataField("sprite")]
         private string? _sprite;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Atmos/Visualizers/GasAnalyzerVisualizer.cs

@@ -2,6 +2,7 @@
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Atmos.Visualizers
@@ -18,7 +19,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }

Content.Client/Atmos/Visualizers/GasCanisterVisualizer.cs

@@ -16,7 +16,7 @@ namespace Content.Client.Atmos.Visualizers
         [DataField("insertedTankState")]
         private readonly string _insertedTankState = string.Empty;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
@@ -32,7 +32,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }

Content.Client/Atmos/Visualizers/GasPortableVisualizer.cs

@@ -13,7 +13,7 @@ namespace Content.Client.Atmos.Visualizers
         [DataField("stateConnected")]
         private string? _stateConnected;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
@@ -30,7 +30,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }

Content.Client/Atmos/Visualizers/PipeConnectorVisualizer.cs

@@ -37,11 +37,12 @@ namespace Content.Client.Atmos.Visualizers
                 Logger.Error($"{nameof(PipeConnectorVisualizer)} could not load to load RSI {rsiString}.");
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
-            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent<ISpriteComponent?>(entity, out var sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent<ISpriteComponent?>(entity, out var sprite))
                 return;
 
             if (_connectorRsi == null)
@@ -52,7 +53,7 @@ namespace Content.Client.Atmos.Visualizers
                 sprite.LayerMapReserveBlank(layerKey);
                 var layer = sprite.LayerMapGet(layerKey);
                 sprite.LayerSetRSI(layer, _connectorRsi);
-                var layerState = _baseState + ((PipeDirection) layerKey).ToString();
+                var layerState = _baseState + ((PipeDirection) layerKey);
                 sprite.LayerSetState(layer, layerState);
             }
         }
@@ -61,10 +62,11 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent<TransformComponent>(out var xform))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent<TransformComponent>(component.Owner, out var xform))
                 return;
 
-            if (!component.Owner.TryGetComponent<ISpriteComponent>(out var sprite))
+            if (!entities.TryGetComponent<ISpriteComponent>(component.Owner, out var sprite))
                 return;
 
             if (!component.TryGetData(PipeColorVisuals.Color, out Color color))

Content.Client/Atmos/Visualizers/ScrubberVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Atmos.Piping.Unary.Visuals;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 
 namespace Content.Client.Atmos.Visualizers
 {
@@ -18,7 +19,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
                 return;
 
             if (!component.TryGetData(ScrubberVisuals.State, out ScrubberState state))

Content.Client/Atmos/Visualizers/VentPumpVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Atmos.Visuals;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 
 namespace Content.Client.Atmos.Visualizers
 {
@@ -17,7 +18,8 @@ namespace Content.Client.Atmos.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
                 return;
 
             if (!component.TryGetData(VentPumpVisuals.State, out VentPumpState state))

Content.Client/Audio/AmbientSoundSystem.cs

@@ -90,17 +90,17 @@ namespace Content.Client.Audio
             _accumulator -= _cooldown;
 
             var player = _playerManager.LocalPlayer?.ControlledEntity;
-            if (player == null)
+            if (player == default)
             {
                 ClearSounds();
                 return;
             }
 
-            var coordinates = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(player).Coordinates;
+            var coordinates = EntityManager.GetComponent<TransformComponent>(player.Value).Coordinates;
 
             foreach (var (comp, (stream, _)) in _playingSounds.ToArray())
             {
-                if (!comp.Deleted && comp.Enabled && IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(comp.Owner).Coordinates.TryDistance(EntityManager, coordinates, out var range) &&
+                if (!comp.Deleted && comp.Enabled && EntityManager.GetComponent<TransformComponent>(comp.Owner).Coordinates.TryDistance(EntityManager, coordinates, out var range) &&
                     range <= comp.Range)
                 {
                     continue;
@@ -136,11 +136,11 @@ namespace Content.Client.Audio
             foreach (var entity in _lookup.GetEntitiesInRange(coordinates, _maxAmbientRange,
                 LookupFlags.Approximate | LookupFlags.IncludeAnchored))
             {
-                if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out AmbientSoundComponent? ambientComp) ||
+                if (!EntityManager.TryGetComponent(entity, out AmbientSoundComponent? ambientComp) ||
                     _playingSounds.ContainsKey(ambientComp) ||
                     !ambientComp.Enabled ||
                     // We'll also do this crude distance check because it's what we're doing in the active loop above.
-                    !IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).Coordinates.TryDistance(EntityManager, coordinates, out var range) ||
+                    !EntityManager.GetComponent<TransformComponent>(entity).Coordinates.TryDistance(EntityManager, coordinates, out var range) ||
                     range > ambientComp.Range - RangeBuffer)
                 {
                     continue;

Content.Client/Body/UI/BodyScannerBoundUserInterface.cs

@@ -15,7 +15,7 @@ namespace Content.Client.Body.UI
         private BodyScannerDisplay? _display;
 
         [ViewVariables]
-        private IEntity? _entity;
+        private EntityUid _entity;
 
         public BodyScannerBoundUserInterface(ClientUserInterfaceComponent owner, object uiKey) : base(owner, uiKey) { }
 
@@ -36,7 +36,7 @@ namespace Content.Client.Body.UI
                 return;
             }
 
-            if (!IoCManager.Resolve<IEntityManager>().TryGetEntity(scannerState.Uid, out _entity))
+            if (!IoCManager.Resolve<IEntityManager>().EntityExists(scannerState.Uid))
             {
                 throw new ArgumentException($"Received an invalid entity with id {scannerState.Uid} for body scanner with id {Owner.Owner} at {IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(Owner.Owner).MapPosition}");
             }

Content.Client/Body/UI/BodyScannerDisplay.cs

@@ -1,6 +1,5 @@
 using System.Linq;
 using Content.Shared.Body.Components;
-using Content.Shared.Body.Part;
 using Content.Shared.Damage;
 using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
@@ -14,7 +13,7 @@ namespace Content.Client.Body.UI
 {
     public sealed class BodyScannerDisplay : SS14Window
     {
-        private IEntity? _currentEntity;
+        private EntityUid _currentEntity;
         private SharedBodyPartComponent? _currentBodyPart;
 
         public BodyScannerDisplay(BodyScannerBoundUserInterface owner)
@@ -103,7 +102,7 @@ namespace Content.Client.Body.UI
 
         private RichTextLabel MechanismInfoLabel { get; }
 
-        public void UpdateDisplay(IEntity entity)
+        public void UpdateDisplay(EntityUid entity)
         {
             if(entity == null)
                 return;

Content.Client/Botany/PlantHolderVisualizer.cs

@@ -10,7 +10,7 @@ namespace Content.Client.Botany
     [UsedImplicitly]
     public class PlantHolderVisualizer : AppearanceVisualizer
     {
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Buckle/BuckleComponent.cs

@@ -30,7 +30,7 @@ namespace Content.Client.Buckle
             _buckled = buckle.Buckled;
             LastEntityBuckledTo = buckle.LastEntityBuckledTo;
             DontCollide = buckle.DontCollide;
-            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(OwnerUid, out SpriteComponent? ownerSprite))
+            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(Owner, out SpriteComponent? ownerSprite))
             {
                 return;
             }

Content.Client/Cabinet/ItemCabinetVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Cabinet;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Cabinet
@@ -19,7 +20,8 @@ namespace Content.Client.Cabinet
         {
             base.OnChangeData(component);
 
-            if (component.Owner.TryGetComponent<SpriteComponent>(out var sprite)
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (entities.TryGetComponent(component.Owner, out SpriteComponent sprite)
                 && component.TryGetData(ItemCabinetVisuals.IsOpen, out bool isOpen)
                 && component.TryGetData(ItemCabinetVisuals.ContainsItem, out bool contains))
             {

Content.Client/CharacterAppearance/Systems/HumanoidAppearanceSystem.cs

@@ -50,7 +50,7 @@ namespace Content.Client.CharacterAppearance.Systems
             {
                 foreach (var (part, _) in body.Parts)
                 {
-                    if (EntityManager.TryGetComponent(part.OwnerUid, out SpriteComponent? partSprite))
+                    if (EntityManager.TryGetComponent(part.Owner, out SpriteComponent? partSprite))
                     {
                         partSprite!.Color = component.Appearance.SkinColor;
                     }
@@ -113,7 +113,7 @@ namespace Content.Client.CharacterAppearance.Systems
                 return;
             }
 
-            if (!entityManager.HasComponent<SpriteComponent>(args.Args.Part.OwnerUid))
+            if (!entityManager.HasComponent<SpriteComponent>(args.Args.Part.Owner))
             {
                 return;
             }
@@ -136,7 +136,7 @@ namespace Content.Client.CharacterAppearance.Systems
                 return;
             }
 
-            if (!EntityManager.HasComponent<SpriteComponent>(args.Args.Part.OwnerUid))
+            if (!EntityManager.HasComponent<SpriteComponent>(args.Args.Part.Owner))
             {
                 return;
             }

Content.Client/CharacterInterface/CharacterInterfaceSystem.cs

@@ -37,8 +37,8 @@ namespace Content.Client.CharacterInterface
 
         private void HandleOpenCharacterMenu()
         {
-            if (_playerManager.LocalPlayer?.ControlledEntity == null
+            if (_playerManager.LocalPlayer?.ControlledEntity == default
-                || !IoCManager.Resolve<IEntityManager>().TryGetComponent(_playerManager.LocalPlayer.ControlledEntity, out CharacterInterfaceComponent? characterInterface))
+                || !EntityManager.TryGetComponent(_playerManager.LocalPlayer.ControlledEntity, out CharacterInterfaceComponent? characterInterface))
             {
                 return;
             }

Content.Client/Chat/Managers/ChatManager.cs

@@ -231,7 +231,9 @@ namespace Content.Client.Chat.Managers
             ChatPermissionsUpdated?.Invoke(new ChatPermissionsUpdatedEventArgs {OldSelectableChannels = oldSelectable});
         }
 
-        public bool IsGhost => _playerManager.LocalPlayer?.ControlledEntity is {} uid && _entityManager.HasComponent<GhostComponent>(uid);
+        public bool IsGhost => _playerManager.LocalPlayer?.ControlledEntity is {} uid &&
+                               uid.IsValid() &&
+                               _entityManager.HasComponent<GhostComponent>(uid);
 
         public void FrameUpdate(FrameEventArgs delta)
         {
@@ -241,11 +243,11 @@ namespace Content.Client.Chat.Managers
                 return;
             }
 
-            foreach (var (entityUid, queueData) in _queuedSpeechBubbles.ShallowClone())
+            foreach (var (entity, queueData) in _queuedSpeechBubbles.ShallowClone())
             {
-                if (!_entityManager.TryGetEntity(entityUid, out var entity))
+                if (!_entityManager.EntityExists(entity))
                 {
-                    _queuedSpeechBubbles.Remove(entityUid);
+                    _queuedSpeechBubbles.Remove(entity);
                     continue;
                 }
 
@@ -257,7 +259,7 @@ namespace Content.Client.Chat.Managers
 
                 if (queueData.MessageQueue.Count == 0)
                 {
-                    _queuedSpeechBubbles.Remove(entityUid);
+                    _queuedSpeechBubbles.Remove(entity);
                     continue;
                 }
 
@@ -412,7 +414,7 @@ namespace Content.Client.Chat.Managers
 
         private void AddSpeechBubble(MsgChatMessage msg, SpeechBubble.SpeechType speechType)
         {
-            if (!_entityManager.TryGetEntity(msg.SenderEntity, out var entity))
+            if (!_entityManager.EntityExists(msg.SenderEntity))
             {
                 Logger.WarningS("chat", "Got local chat message with invalid sender entity: {0}", msg.SenderEntity);
                 return;
@@ -422,7 +424,7 @@ namespace Content.Client.Chat.Managers
 
             foreach (var message in messages)
             {
-                EnqueueSpeechBubble(entity, message, speechType);
+                EnqueueSpeechBubble(msg.SenderEntity, message, speechType);
             }
         }
 
@@ -472,7 +474,7 @@ namespace Content.Client.Chat.Managers
             return messages;
         }
 
-        private void EnqueueSpeechBubble(IEntity entity, string contents, SpeechBubble.SpeechType speechType)
+        private void EnqueueSpeechBubble(EntityUid entity, string contents, SpeechBubble.SpeechType speechType)
         {
             // Don't enqueue speech bubbles for other maps. TODO: Support multiple viewports/maps?
             if (IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).MapID != _eyeManager.CurrentMap)
@@ -491,7 +493,7 @@ namespace Content.Client.Chat.Managers
             });
         }
 
-        private void CreateSpeechBubble(IEntity entity, SpeechBubbleData speechData)
+        private void CreateSpeechBubble(EntityUid entity, SpeechBubbleData speechData)
         {
             var bubble =
                 SpeechBubble.CreateSpeechBubble(speechData.Type, speechData.Message, entity, _eyeManager, this);

Content.Client/Chat/UI/SpeechBubble.cs

@@ -36,7 +36,7 @@ namespace Content.Client.Chat.UI
         private const float EntityVerticalOffset = 0.5f;
 
         private readonly IEyeManager _eyeManager;
-        private readonly IEntity _senderEntity;
+        private readonly EntityUid _senderEntity;
         private readonly IChatManager _chatManager;
 
         private float _timeLeft = TotalTime;
@@ -46,7 +46,7 @@ namespace Content.Client.Chat.UI
 
         public float ContentHeight { get; private set; }
 
-        public static SpeechBubble CreateSpeechBubble(SpeechType type, string text, IEntity senderEntity, IEyeManager eyeManager, IChatManager chatManager)
+        public static SpeechBubble CreateSpeechBubble(SpeechType type, string text, EntityUid senderEntity, IEyeManager eyeManager, IChatManager chatManager)
         {
             switch (type)
             {
@@ -61,7 +61,7 @@ namespace Content.Client.Chat.UI
             }
         }
 
-        public SpeechBubble(string text, IEntity senderEntity, IEyeManager eyeManager, IChatManager chatManager)
+        public SpeechBubble(string text, EntityUid senderEntity, IEyeManager eyeManager, IChatManager chatManager)
         {
             _chatManager = chatManager;
             _senderEntity = senderEntity;
@@ -162,7 +162,7 @@ namespace Content.Client.Chat.UI
     public class EmoteSpeechBubble : SpeechBubble
 
     {
-        public EmoteSpeechBubble(string text, IEntity senderEntity, IEyeManager eyeManager, IChatManager chatManager)
+        public EmoteSpeechBubble(string text, EntityUid senderEntity, IEyeManager eyeManager, IChatManager chatManager)
             : base(text, senderEntity, eyeManager, chatManager)
         {
         }
@@ -188,7 +188,7 @@ namespace Content.Client.Chat.UI
 
     public class SaySpeechBubble : SpeechBubble
     {
-        public SaySpeechBubble(string text, IEntity senderEntity, IEyeManager eyeManager, IChatManager chatManager)
+        public SaySpeechBubble(string text, EntityUid senderEntity, IEyeManager eyeManager, IChatManager chatManager)
             : base(text, senderEntity, eyeManager, chatManager)
         {
         }

Content.Client/Chemistry/Visualizers/FoamVisualizer.cs

@@ -4,6 +4,7 @@ using JetBrains.Annotations;
 using Robust.Client.Animations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 using Robust.Shared.Serialization;
 using Robust.Shared.Serialization.Manager.Attributes;
@@ -36,11 +37,12 @@ namespace Content.Client.Chemistry.Visualizers
         {
             base.OnChangeData(component);
 
+            var entities = IoCManager.Resolve<IEntityManager>();
             if (component.TryGetData<bool>(FoamVisuals.State, out var state))
             {
                 if (state)
                 {
-                    if (component.Owner.TryGetComponent(out AnimationPlayerComponent? animPlayer))
+                    if (entities.TryGetComponent(component.Owner, out AnimationPlayerComponent? animPlayer))
                     {
                         if (!animPlayer.HasRunningAnimation(AnimationKey))
                             animPlayer.Play(_foamDissolve, AnimationKey);
@@ -50,7 +52,7 @@ namespace Content.Client.Chemistry.Visualizers
 
             if (component.TryGetData<Color>(FoamVisuals.Color, out var color))
             {
-                if (component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+                if (entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
                 {
                     sprite.Color = color;
                 }

Content.Client/Chemistry/Visualizers/SmokeVisualizer.cs

@@ -2,6 +2,7 @@
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 
 namespace Content.Client.Chemistry.Visualizers
@@ -13,9 +14,10 @@ namespace Content.Client.Chemistry.Visualizers
         {
             base.OnChangeData(component);
 
+            var entities = IoCManager.Resolve<IEntityManager>();
             if (component.TryGetData<Color>(SmokeVisuals.Color, out var color))
             {
-                if (component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+                if (entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
                 {
                     sprite.Color = color;
                 }

Content.Client/Chemistry/Visualizers/SolutionContainerVisualizer.cs

@@ -3,6 +3,7 @@ using Content.Shared.Chemistry;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 using Robust.Shared.Serialization.Manager.Attributes;
 
@@ -25,7 +26,8 @@ namespace Content.Client.Chemistry.Visualizers
             if (!component.TryGetData(SolutionContainerVisuals.VisualState,
                 out SolutionContainerVisualState state)) return;
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite)) return;
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite)) return;
             if (!sprite.LayerMapTryGet(_layer, out var fillLayer)) return;
 
             var fillPercent = state.FilledVolumePercent;

Content.Client/CombatMode/CombatModeSystem.cs

@@ -4,7 +4,6 @@ using Content.Shared.Targeting;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Client.Player;
-using Robust.Shared.GameObjects;
 using Robust.Shared.Input.Binding;
 using Robust.Shared.IoC;
 
@@ -35,7 +34,7 @@ namespace Content.Client.CombatMode
         public bool IsInCombatMode()
         {
             var entity = _playerManager.LocalPlayer?.ControlledEntity;
-            if (entity == null || !IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out CombatModeComponent? combatMode))
+            if (entity == default || !EntityManager.TryGetComponent(entity.Value, out CombatModeComponent? combatMode))
             {
                 return false;
             }

Content.Client/Computer/ComputerVisualizer.cs

@@ -20,7 +20,7 @@ namespace Content.Client.Computer
         private string BodyBrokenState = "broken";
         private string ScreenBroken = "computer_broken";
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Construction/ConstructionSystem.cs

@@ -17,7 +17,6 @@ using Robust.Shared.Map;
 using Robust.Shared.Maths;
 using Robust.Shared.Prototypes;
 
-
 namespace Content.Client.Construction
 {
     /// <summary>
@@ -111,7 +110,7 @@ namespace Content.Client.Construction
 
         private void HandlePlayerAttached(PlayerAttachSysMessage msg)
         {
-            var available = IsCrafingAvailable(msg.AttachedEntity);
+            var available = IsCraftingAvailable(msg.AttachedEntity);
             UpdateCraftingAvailability(available);
         }
 
@@ -131,9 +130,9 @@ namespace Content.Client.Construction
             CraftingEnabled = available;
         }
 
-        private static bool IsCrafingAvailable(IEntity? entity)
+        private static bool IsCraftingAvailable(EntityUid? entity)
         {
-            if (entity == null)
+            if (entity == default)
                 return false;
 
             // TODO: Decide if entity can craft, using capabilities or something
@@ -145,9 +144,7 @@ namespace Content.Client.Construction
             if (!args.EntityUid.IsValid() || !args.EntityUid.IsClientSide())
                 return false;
 
-            var entity = EntityManager.GetEntity(args.EntityUid);
+            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent<ConstructionGhostComponent?>(args.EntityUid, out var ghostComp))
-
-            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent<ConstructionGhostComponent?>(entity, out var ghostComp))
                 return false;
 
             TryStartConstruction(ghostComp.GhostId);
@@ -159,10 +156,14 @@ namespace Content.Client.Construction
         /// </summary>
         public void SpawnGhost(ConstructionPrototype prototype, EntityCoordinates loc, Direction dir)
         {
-            var user = _playerManager.LocalPlayer?.ControlledEntity;
+            if (_playerManager.LocalPlayer?.ControlledEntity is not { } user ||
+                !user.IsValid())
+            {
+                return;
+            }
 
             // This InRangeUnobstructed should probably be replaced with "is there something blocking us in that tile?"
-            if (user == null || GhostPresent(loc) || !user.InRangeUnobstructed(loc, 20f, ignoreInsideBlocker: prototype.CanBuildInImpassable)) return;
+            if (GhostPresent(loc) || !user.InRangeUnobstructed(loc, 20f, ignoreInsideBlocker: prototype.CanBuildInImpassable)) return;
 
             foreach (var condition in prototype.Conditions)
             {
@@ -226,7 +227,7 @@ namespace Content.Client.Construction
         {
             if (_ghosts.TryGetValue(ghostId, out var ghost))
             {
-                IoCManager.Resolve<IEntityManager>().QueueDeleteEntity((EntityUid) ghost.Owner);
+                IoCManager.Resolve<IEntityManager>().QueueDeleteEntity(ghost.Owner);
                 _ghosts.Remove(ghostId);
             }
         }
@@ -238,7 +239,7 @@ namespace Content.Client.Construction
         {
             foreach (var (_, ghost) in _ghosts)
             {
-                IoCManager.Resolve<IEntityManager>().QueueDeleteEntity((EntityUid) ghost.Owner);
+                IoCManager.Resolve<IEntityManager>().QueueDeleteEntity(ghost.Owner);
             }
 
             _ghosts.Clear();

Content.Client/ContextMenu/UI/EntityMenuElement.cs

@@ -1,4 +1,3 @@
-using Content.Client.Stylesheets;
 using Robust.Client.GameObjects;
 using Robust.Client.UserInterface.Controls;
 using Robust.Shared.GameObjects;
@@ -14,7 +13,7 @@ namespace Content.Client.ContextMenu.UI
         /// <summary>
         ///     The entity that can be accessed by interacting with this element.
         /// </summary>
-        public IEntity? Entity;
+        public EntityUid Entity;
 
         /// <summary>
         ///     How many entities are accessible through this element's sub-menus.
@@ -24,10 +23,10 @@ namespace Content.Client.ContextMenu.UI
         /// </remarks>
         public int Count;
 
-        public Label CountLabel;
+        public readonly Label CountLabel;
-        public SpriteView EntityIcon = new SpriteView { OverrideDirection = Direction.South};
+        public readonly SpriteView EntityIcon = new() { OverrideDirection = Direction.South};
 
-        public EntityMenuElement(IEntity? entity = null) : base()
+        public EntityMenuElement(EntityUid entity = default)
         {
             CountLabel = new Label { StyleClasses = { StyleClassEntityMenuCountText } };
             Icon.AddChild(new LayoutContainer() { Children = { EntityIcon, CountLabel } });
@@ -37,7 +36,7 @@ namespace Content.Client.ContextMenu.UI
             LayoutContainer.SetGrowVertical(CountLabel, LayoutContainer.GrowDirection.Begin);
 
             Entity = entity;
-            if (Entity != null)
+            if (Entity != default)
             {
                 Count = 1;
                 CountLabel.Visible = false;
@@ -48,7 +47,7 @@ namespace Content.Client.ContextMenu.UI
         protected override void Dispose(bool disposing)
         {
             base.Dispose(disposing);
-            Entity = null;
+            Entity = default;
             Count = 0;
         }
 
@@ -56,12 +55,12 @@ namespace Content.Client.ContextMenu.UI
         ///     Update the icon and text of this element based on the given entity or this element's own entity if none
         ///     is provided.
         /// </summary>
-        public void UpdateEntity(IEntity? entity = null)
+        public void UpdateEntity(EntityUid entity = default)
         {
-            if (Entity != null && IoCManager.Resolve<IEntityManager>().EntityExists(Entity))
+            if (Entity != default && IoCManager.Resolve<IEntityManager>().EntityExists(Entity) && !entity.Valid)
-                entity ??= Entity;
+                entity = Entity;
 
-            if (entity == null)
+            if (entity == default)
             {
                 Text = string.Empty;
                 return;

Content.Client/ContextMenu/UI/EntityMenuPresenter.cs

@@ -18,8 +18,8 @@ using Robust.Shared.Input.Binding;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
 using Robust.Shared.Maths;
-using Robust.Shared.Prototypes;
 using Robust.Shared.Timing;
+
 namespace Content.Client.ContextMenu.UI
 {
     /// <summary>
@@ -51,7 +51,7 @@ namespace Content.Client.ContextMenu.UI
         /// <remarks>
         ///     This is used remove GUI elements when the entities are deleted. or leave the LOS.
         /// </remarks>
-        public Dictionary<IEntity, EntityMenuElement> Elements = new();
+        public Dictionary<EntityUid, EntityMenuElement> Elements = new();
 
         public EntityMenuPresenter(VerbSystem verbSystem) : base()
         {
@@ -77,7 +77,7 @@ namespace Content.Client.ContextMenu.UI
         /// <summary>
         ///     Given a list of entities, sort them into groups and them to a new entity menu.
         /// </summary>
-        public void OpenRootMenu(List<IEntity> entities)
+        public void OpenRootMenu(List<EntityUid> entities)
         {
             // close any old menus first.
             if (RootMenu.Visible)
@@ -101,8 +101,12 @@ namespace Content.Client.ContextMenu.UI
 
             // get an entity associated with this element
             var entity = entityElement.Entity;
-            entity ??= GetFirstEntityOrNull(element.SubMenu);
+            if (!entity.Valid)
-            if (entity == null)
+            {
+                entity = GetFirstEntityOrNull(element.SubMenu);
+            }
+
+            if (!entity.Valid)
                 return;
 
             // open verb menu?
@@ -173,9 +177,8 @@ namespace Content.Client.ContextMenu.UI
             if (!RootMenu.Visible)
                 return;
 
-            var player = _playerManager.LocalPlayer?.ControlledEntity;
+            if (_playerManager.LocalPlayer?.ControlledEntity is not { } player ||
-
+                !player.IsValid())
-            if (player == null)
                 return;
 
             // Do we need to do in-range unOccluded checks?
@@ -193,7 +196,7 @@ namespace Content.Client.ContextMenu.UI
         ///     Add menu elements for a list of grouped entities;
         /// </summary>
         /// <param name="entityGroups"> A list of entity groups. Entities are grouped together based on prototype.</param>
-        private void AddToUI(List<List<IEntity>> entityGroups)
+        private void AddToUI(List<List<EntityUid>> entityGroups)
         {
             // If there is only a single group. We will just directly list individual entities
             if (entityGroups.Count == 1)
@@ -226,7 +229,7 @@ namespace Content.Client.ContextMenu.UI
         /// <summary>
         ///     Given a group of entities, add a menu element that has a pop-up sub-menu listing group members
         /// </summary>
-        private void AddGroupToUI(List<IEntity> group)
+        private void AddGroupToUI(List<EntityUid> group)
         {
             EntityMenuElement element = new();
             ContextMenuPopup subMenu = new(this, element);
@@ -245,7 +248,7 @@ namespace Content.Client.ContextMenu.UI
         /// <summary>
         ///     Remove an entity from the entity context menu.
         /// </summary>
-        private void RemoveEntity(IEntity entity)
+        private void RemoveEntity(EntityUid entity)
         {
             // find the element associated with this entity
             if (!Elements.TryGetValue(entity, out var element))
@@ -323,17 +326,17 @@ namespace Content.Client.ContextMenu.UI
         /// <summary>
         ///     Recursively look through a sub-menu and return the first entity.
         /// </summary>
-        private IEntity? GetFirstEntityOrNull(ContextMenuPopup? menu)
+        private EntityUid GetFirstEntityOrNull(ContextMenuPopup? menu)
         {
             if (menu == null)
-                return null;
+                return default;
 
             foreach (var element in menu.MenuBody.Children)
             {
                 if (element is not EntityMenuElement entityElement)
                     continue;
 
-                if (entityElement.Entity != null)
+                if (entityElement.Entity != default)
                 {
                     if (!((!IoCManager.Resolve<IEntityManager>().EntityExists(entityElement.Entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entityElement.Entity).EntityLifeStage) >= EntityLifeStage.Deleted))
                         return entityElement.Entity;
@@ -342,11 +345,11 @@ namespace Content.Client.ContextMenu.UI
 
                 // if the element has no entity, its a group of entities with another attached sub-menu.
                 var entity = GetFirstEntityOrNull(entityElement.SubMenu);
-                if (entity != null)
+                if (entity != default)
                     return entity;
             }
 
-            return null;
+            return default;
         }
 
         public override void OpenSubMenu(ContextMenuElement element)

Content.Client/ContextMenu/UI/EntityMenuPresenterGrouping.cs

@@ -4,7 +4,6 @@ using System.Linq;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
-using Robust.Shared.Prototypes;
 
 namespace Content.Client.ContextMenu.UI
 {
@@ -18,7 +17,7 @@ namespace Content.Client.ContextMenu.UI
             GroupingContextMenuType = obj;
         }
 
-        private List<List<IEntity>> GroupEntities(IEnumerable<IEntity> entities, int depth = 0)
+        private List<List<EntityUid>> GroupEntities(IEnumerable<EntityUid> entities, int depth = 0)
         {
             if (GroupingContextMenuType == 0)
             {
@@ -32,9 +31,9 @@ namespace Content.Client.ContextMenu.UI
             }
         }
 
-        private sealed class PrototypeAndStatesContextMenuComparer : IEqualityComparer<IEntity>
+        private sealed class PrototypeAndStatesContextMenuComparer : IEqualityComparer<EntityUid>
         {
-            private static readonly List<Func<IEntity, IEntity, bool>> EqualsList = new()
+            private static readonly List<Func<EntityUid, EntityUid, bool>> EqualsList = new()
             {
                 (a, b) => IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(a).EntityPrototype!.ID == IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(b).EntityPrototype!.ID,
                 (a, b) =>
@@ -51,7 +50,7 @@ namespace Content.Client.ContextMenu.UI
                     return xStates.OrderBy(t => t).SequenceEqual(yStates.OrderBy(t => t));
                 },
             };
-            private static readonly List<Func<IEntity, int>> GetHashCodeList = new()
+            private static readonly List<Func<EntityUid, int>> GetHashCodeList = new()
             {
                 e => EqualityComparer<string>.Default.GetHashCode(IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(e).EntityPrototype!.ID),
                 e =>
@@ -73,17 +72,17 @@ namespace Content.Client.ContextMenu.UI
                 _depth = step > Count ? Count : step;
             }
 
-            public bool Equals(IEntity? x, IEntity? y)
+            public bool Equals(EntityUid x, EntityUid y)
             {
-                if (x == null)
+                if (x == default)
                 {
-                    return y == null;
+                    return y == default;
                 }
 
-                return y != null && EqualsList[_depth](x, y);
+                return y != default && EqualsList[_depth](x, y);
             }
 
-            public int GetHashCode(IEntity e)
+            public int GetHashCode(EntityUid e)
             {
                 return GetHashCodeList[_depth](e);
             }

Content.Client/Conveyor/Visualizers/ConveyorVisualizer.cs

@@ -3,6 +3,7 @@ using Content.Shared.Conveyor;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Conveyor.Visualizers
@@ -21,7 +22,8 @@ namespace Content.Client.Conveyor.Visualizers
 
         private void ChangeState(AppearanceComponent appearance)
         {
-            if (!appearance.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(appearance.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }
@@ -40,7 +42,7 @@ namespace Content.Client.Conveyor.Visualizers
             }
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Conveyor/Visualizers/TwoWayLeverVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.MachineLinking;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Conveyor.Visualizers
@@ -20,7 +21,8 @@ namespace Content.Client.Conveyor.Visualizers
 
         private void ChangeState(AppearanceComponent appearance)
         {
-            if (!appearance.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(appearance.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }
@@ -38,7 +40,7 @@ namespace Content.Client.Conveyor.Visualizers
             sprite.LayerSetState(0, texture);
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Damage/DamageVisualizer.cs

@@ -195,7 +195,7 @@ namespace Content.Client.Damage
             public readonly string? Color;
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
@@ -207,7 +207,7 @@ namespace Content.Client.Damage
                 InitializeVisualizer(entity, damageData);
         }
 
-        private void VerifyVisualizerSetup(IEntity entity, DamageVisualizerDataComponent damageData)
+        private void VerifyVisualizerSetup(EntityUid entity, DamageVisualizerDataComponent damageData)
         {
             if (_thresholds.Count < 1)
             {
@@ -289,7 +289,7 @@ namespace Content.Client.Damage
             }
         }
 
-        private void InitializeVisualizer(IEntity entity, DamageVisualizerDataComponent damageData)
+        private void InitializeVisualizer(EntityUid entity, DamageVisualizerDataComponent damageData)
         {
             if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out SpriteComponent? spriteComponent)
                 || !IoCManager.Resolve<IEntityManager>().TryGetComponent<DamageableComponent?>(entity, out var damageComponent)
@@ -504,7 +504,8 @@ namespace Content.Client.Damage
 
         public override void OnChangeData(AppearanceComponent component)
         {
-            if (!component.Owner.TryGetComponent<DamageVisualizerDataComponent>(out var damageData))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out DamageVisualizerDataComponent damageData))
                 return;
 
             if (!damageData.Valid)
@@ -525,8 +526,9 @@ namespace Content.Client.Damage
 
         private void HandleDamage(AppearanceComponent component, DamageVisualizerDataComponent damageData)
         {
-            if (!component.Owner.TryGetComponent<SpriteComponent>(out var spriteComponent)
+            var entities = IoCManager.Resolve<IEntityManager>();
-                || !component.Owner.TryGetComponent<DamageableComponent>(out var damageComponent))
+            if (!entities.TryGetComponent(component.Owner, out SpriteComponent spriteComponent)
+                || !entities.TryGetComponent(component.Owner, out DamageableComponent damageComponent))
                 return;
 
             if (_targetLayers != null && _damageOverlayGroups != null)

Content.Client/Disposal/Visualizers/DisposalUnitVisualizer.cs

@@ -70,7 +70,8 @@ namespace Content.Client.Disposal.Visualizers
                 return;
             }
 
-            if (!appearance.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(appearance.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }
@@ -144,7 +145,7 @@ namespace Content.Client.Disposal.Visualizers
             }
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Disposal/Visualizers/DisposalVisualizer.cs

@@ -23,7 +23,8 @@ namespace Content.Client.Disposal.Visualizers
 
         private void ChangeState(AppearanceComponent appearance)
         {
-            if (!appearance.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(appearance.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }
@@ -53,7 +54,7 @@ namespace Content.Client.Disposal.Visualizers
             }
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/DoAfter/DoAfterSystem.cs

@@ -31,7 +31,7 @@ namespace Content.Client.DoAfter
         /// </summary>
         public const float ExcessTime = 0.5f;
 
-        private IEntity? _attachedEntity;
+        private EntityUid _attachedEntity;
 
         public override void Initialize()
         {
@@ -51,7 +51,7 @@ namespace Content.Client.DoAfter
             var currentTime = _gameTiming.CurTime;
 
             // Can't see any I guess?
-            if (_attachedEntity == null || (!IoCManager.Resolve<IEntityManager>().EntityExists(_attachedEntity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_attachedEntity).EntityLifeStage) >= EntityLifeStage.Deleted)
+            if (_attachedEntity == default || (!EntityManager.EntityExists(_attachedEntity) ? EntityLifeStage.Deleted : EntityManager.GetComponent<MetaDataComponent>(_attachedEntity).EntityLifeStage) >= EntityLifeStage.Deleted)
                 return;
 
             var viewbox = _eyeManager.GetWorldViewport().Enlarged(2.0f);
@@ -59,23 +59,23 @@ namespace Content.Client.DoAfter
             foreach (var comp in EntityManager.EntityQuery<DoAfterComponent>(true))
             {
                 var doAfters = comp.DoAfters.ToList();
-                var compPos = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(comp.Owner).WorldPosition;
+                var compPos = EntityManager.GetComponent<TransformComponent>(comp.Owner).WorldPosition;
 
                 if (doAfters.Count == 0 ||
-                    IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(comp.Owner).MapID != IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_attachedEntity).MapID ||
+                    EntityManager.GetComponent<TransformComponent>(comp.Owner).MapID != EntityManager.GetComponent<TransformComponent>(_attachedEntity).MapID ||
                     !viewbox.Contains(compPos))
                 {
                     comp.Disable();
                     continue;
                 }
 
-                var range = (compPos - IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_attachedEntity).WorldPosition).Length +
+                var range = (compPos - EntityManager.GetComponent<TransformComponent>(_attachedEntity).WorldPosition).Length +
                             0.01f;
 
                 if (comp.Owner != _attachedEntity &&
                     !ExamineSystemShared.InRangeUnOccluded(
-                        IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_attachedEntity).MapPosition,
+                        EntityManager.GetComponent<TransformComponent>(_attachedEntity).MapPosition,
-                        IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(comp.Owner).MapPosition, range,
+                        EntityManager.GetComponent<TransformComponent>(comp.Owner).MapPosition, range,
                         entity => entity == comp.Owner || entity == _attachedEntity))
                 {
                     comp.Disable();
@@ -84,7 +84,7 @@ namespace Content.Client.DoAfter
 
                 comp.Enable();
 
-                var userGrid = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(comp.Owner).Coordinates;
+                var userGrid = EntityManager.GetComponent<TransformComponent>(comp.Owner).Coordinates;
 
                 // Check cancellations / finishes
                 foreach (var (id, doAfter) in doAfters)
@@ -116,8 +116,8 @@ namespace Content.Client.DoAfter
 
                     if (doAfter.BreakOnTargetMove)
                     {
-                        if (EntityManager.TryGetEntity(doAfter.TargetUid, out var targetEntity) &&
+                        if (EntityManager.EntityExists(doAfter.TargetUid) &&
-                            !IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(targetEntity).Coordinates.InRange(EntityManager, doAfter.TargetGrid,
+                            !EntityManager.GetComponent<TransformComponent>(doAfter.TargetUid).Coordinates.InRange(EntityManager, doAfter.TargetGrid,
                                 doAfter.MovementThreshold))
                         {
                             comp.Cancel(id, currentTime);

Content.Client/DoAfter/UI/DoAfterGui.cs

@@ -27,7 +27,7 @@ namespace Content.Client.DoAfter.UI
         // We'll store cancellations for a little bit just so we can flash the graphic to indicate it's cancelled
         private readonly Dictionary<byte, TimeSpan> _cancelledDoAfters = new();
 
-        public IEntity? AttachedEntity { get; set; }
+        public EntityUid AttachedEntity { get; set; }
         private ScreenCoordinates _playerPosition;
 
         public DoAfterGui()
@@ -146,14 +146,8 @@ namespace Content.Client.DoAfter.UI
         {
             base.FrameUpdate(args);
 
-            IEntity? tempQualifier = AttachedEntity;
+            if (!AttachedEntity.IsValid() ||
-            if (tempQualifier != null)
+                !_entityManager.TryGetComponent(AttachedEntity, out DoAfterComponent? doAfterComponent))
-            {
-                IoCManager.Resolve<IEntityManager>().EntityExists(tempQualifier);
-            }
-
-            if (RETURNED_VALUE != true ||
-                !IoCManager.Resolve<IEntityManager>().TryGetComponent(AttachedEntity, out DoAfterComponent? doAfterComponent))
             {
                 Visible = false;
                 return;

Content.Client/Doors/AirlockVisualizer.cs

@@ -1,8 +1,6 @@
 using System;
 using Content.Client.Wires.Visualizers;
-using Content.Shared.Audio;
 using Content.Shared.Doors;
-using Content.Shared.Sound;
 using JetBrains.Annotations;
 using Robust.Client.Animations;
 using Robust.Client.GameObjects;
@@ -110,7 +108,7 @@ namespace Content.Client.Doors
             }
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             if (!IoCManager.Resolve<IEntityManager>().HasComponent<AnimationPlayerComponent>(entity))
             {

Content.Client/DragDrop/DragDropSystem.cs

@@ -54,9 +54,9 @@ namespace Content.Client.DragDrop
 
         // entity performing the drag action
 
-        private IEntity? _dragger;
+        private EntityUid _dragger;
         private readonly List<IDraggable> _draggables = new();
-        private IEntity? _dragShadow;
+        private EntityUid _dragShadow;
 
         // time since mouse down over the dragged entity
         private float _mouseDownTime;
@@ -68,7 +68,7 @@ namespace Content.Client.DragDrop
         // can ignore any events sent to this system
         private bool _isReplaying;
 
-        private DragDropHelper<IEntity> _dragDropHelper = default!;
+        private DragDropHelper<EntityUid> _dragDropHelper = default!;
 
         private ShaderInstance? _dropTargetInRangeShader;
         private ShaderInstance? _dropTargetOutOfRangeShader;
@@ -77,7 +77,7 @@ namespace Content.Client.DragDrop
 
         public override void Initialize()
         {
-            _dragDropHelper = new DragDropHelper<IEntity>(OnBeginDrag, OnContinueDrag, OnEndDrag);
+            _dragDropHelper = new DragDropHelper<EntityUid>(OnBeginDrag, OnContinueDrag, OnEndDrag);
 
             _dropTargetInRangeShader = _prototypeManager.Index<ShaderPrototype>(ShaderDropTargetInRange).Instance();
             _dropTargetOutOfRangeShader = _prototypeManager.Index<ShaderPrototype>(ShaderDropTargetOutOfRange).Instance();
@@ -118,33 +118,32 @@ namespace Content.Client.DragDrop
 
         private bool OnUseMouseDown(in PointerInputCmdHandler.PointerInputCmdArgs args)
         {
-            if (args.Session?.AttachedEntity == null)
+            if (args.Session?.AttachedEntity is not {Valid: true} dragger)
             {
                 return false;
             }
 
-            var dragger = args.Session.AttachedEntity;
             // cancel any current dragging if there is one (shouldn't be because they would've had to have lifted
             // the mouse, canceling the drag, but just being cautious)
             _dragDropHelper.EndDrag();
 
             // possibly initiating a drag
             // check if the clicked entity is draggable
-            if (!EntityManager.TryGetEntity(args.EntityUid, out var entity))
+            if (!EntityManager.EntityExists(args.EntityUid))
             {
                 return false;
             }
 
             // check if the entity is reachable
-            if (!_interactionSystem.InRangeUnobstructed(dragger, entity))
+            if (!_interactionSystem.InRangeUnobstructed(dragger, args.EntityUid))
             {
                 return false;
             }
 
             var canDrag = false;
-            foreach (var draggable in IoCManager.Resolve<IEntityManager>().GetComponents<IDraggable>(entity))
+            foreach (var draggable in EntityManager.GetComponents<IDraggable>(args.EntityUid))
             {
-                var dragEventArgs = new StartDragDropEvent(dragger, entity);
+                var dragEventArgs = new StartDragDropEvent(dragger, args.EntityUid);
 
                 if (!draggable.CanStartDrag(dragEventArgs))
                 {
@@ -161,7 +160,7 @@ namespace Content.Client.DragDrop
             }
 
             // wait to initiate a drag
-            _dragDropHelper.MouseDown(entity);
+            _dragDropHelper.MouseDown(args.EntityUid);
             _dragger = dragger;
             _mouseDownTime = 0;
 
@@ -176,19 +175,19 @@ namespace Content.Client.DragDrop
 
         private bool OnBeginDrag()
         {
-            if (_dragDropHelper.Dragged == null || (!IoCManager.Resolve<IEntityManager>().EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted)
+            if (_dragDropHelper.Dragged == default || (!EntityManager.EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : EntityManager.GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted)
             {
                 // something happened to the clicked entity or we moved the mouse off the target so
                 // we shouldn't replay the original click
                 return false;
             }
 
-            if (IoCManager.Resolve<IEntityManager>().TryGetComponent<SpriteComponent?>(_dragDropHelper.Dragged, out var draggedSprite))
+            if (EntityManager.TryGetComponent<SpriteComponent?>(_dragDropHelper.Dragged, out var draggedSprite))
             {
                 // pop up drag shadow under mouse
                 var mousePos = _eyeManager.ScreenToMap(_dragDropHelper.MouseScreenPosition);
                 _dragShadow = EntityManager.SpawnEntity("dragshadow", mousePos);
-                var dragSprite = IoCManager.Resolve<IEntityManager>().GetComponent<SpriteComponent>(_dragShadow);
+                var dragSprite = EntityManager.GetComponent<SpriteComponent>(_dragShadow);
                 dragSprite.CopyFrom(draggedSprite);
                 dragSprite.RenderOrder = EntityManager.CurrentTick.Value;
                 dragSprite.Color = dragSprite.Color.WithAlpha(0.7f);
@@ -196,7 +195,7 @@ namespace Content.Client.DragDrop
                 dragSprite.DrawDepth = (int) DrawDepth.Overlays;
                 if (!dragSprite.NoRotation)
                 {
-                    IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_dragShadow).WorldRotation = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_dragDropHelper.Dragged).WorldRotation;
+                    EntityManager.GetComponent<TransformComponent>(_dragShadow).WorldRotation = EntityManager.GetComponent<TransformComponent>(_dragDropHelper.Dragged).WorldRotation;
                 }
 
                 HighlightTargets();
@@ -207,13 +206,13 @@ namespace Content.Client.DragDrop
             }
 
             Logger.Warning("Unable to display drag shadow for {0} because it" +
-                           " has no sprite component.", IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityName);
+                           " has no sprite component.", EntityManager.GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityName);
             return false;
         }
 
         private bool OnContinueDrag(float frameTime)
         {
-            if (_dragDropHelper.Dragged == null || (!IoCManager.Resolve<IEntityManager>().EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted)
+            if (_dragDropHelper.Dragged == default || (!EntityManager.EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : EntityManager.GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted)
             {
                 return false;
             }
@@ -221,7 +220,7 @@ namespace Content.Client.DragDrop
             DebugTools.AssertNotNull(_dragger);
 
             // still in range of the thing we are dragging?
-            if (!_interactionSystem.InRangeUnobstructed(_dragger!, _dragDropHelper.Dragged))
+            if (!_interactionSystem.InRangeUnobstructed(_dragger, _dragDropHelper.Dragged))
             {
                 return false;
             }
@@ -230,10 +229,10 @@ namespace Content.Client.DragDrop
             var mousePos = _eyeManager.ScreenToMap(_dragDropHelper.MouseScreenPosition);
             // TODO: would use MapPosition instead if it had a setter, but it has no setter.
             // is that intentional, or should we add a setter for Transform.MapPosition?
-            if (_dragShadow == null)
+            if (_dragShadow == default)
                 return false;
 
-            IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_dragShadow).WorldPosition = mousePos.Position;
+            EntityManager.GetComponent<TransformComponent>(_dragShadow).WorldPosition = mousePos.Position;
 
             _targetRecheckTime += frameTime;
             if (_targetRecheckTime > TargetRecheckInterval)
@@ -248,22 +247,22 @@ namespace Content.Client.DragDrop
         private void OnEndDrag()
         {
             RemoveHighlights();
-            if (_dragShadow != null)
+            if (_dragShadow != default)
             {
                 EntityManager.DeleteEntity(_dragShadow);
             }
 
             EntityManager.EventBus.RaiseEvent(EventSource.Local, new OutlineToggleMessage(true));
-            _dragShadow = null;
+            _dragShadow = default;
             _draggables.Clear();
-            _dragger = null;
+            _dragger = default;
             _mouseDownTime = 0;
             _savedMouseDown = null;
         }
 
         private bool OnUseMouseUp(in PointerInputCmdHandler.PointerInputCmdArgs args)
         {
-            if (_dragDropHelper.IsDragging == false || _dragDropHelper.Dragged == null)
+            if (_dragDropHelper.IsDragging == false || _dragDropHelper.Dragged == default)
             {
                 // haven't started the drag yet, quick mouseup, definitely treat it as a normal click by
                 // replaying the original cmd
@@ -287,7 +286,7 @@ namespace Content.Client.DragDrop
                 return false;
             }
 
-            if (_dragger == null)
+            if (_dragger == default)
             {
                 _dragDropHelper.EndDrag();
                 return false;
@@ -295,7 +294,7 @@ namespace Content.Client.DragDrop
 
             // now when ending the drag, we will not replay the click because
             // by this time we've determined the input was actually a drag attempt
-            var range = (args.Coordinates.ToMapPos(EntityManager) - IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(_dragger).MapPosition.Position).Length + 0.01f;
+            var range = (args.Coordinates.ToMapPos(EntityManager) - EntityManager.GetComponent<TransformComponent>(_dragger).MapPosition.Position).Length + 0.01f;
             // tell the server we are dropping if we are over a valid drop target in range.
             // We don't use args.EntityUid here because drag interactions generally should
             // work even if there's something "on top" of the drop target
@@ -330,7 +329,7 @@ namespace Content.Client.DragDrop
                     if (!draggable.CanDrop(dropArgs)) continue;
 
                     // tell the server about the drop attempt
-                    RaiseNetworkEvent(new DragDropRequestEvent(args.Coordinates, _dragDropHelper.Dragged!,
+                    RaiseNetworkEvent(new DragDropRequestEvent(args.Coordinates, _dragDropHelper.Dragged,
                         entity));
 
                     draggable.Drop(dropArgs);
@@ -340,9 +339,11 @@ namespace Content.Client.DragDrop
                 }
             }
 
-            if (outOfRange)
+            if (outOfRange &&
+                _playerManager.LocalPlayer?.ControlledEntity is { } player &&
+                player.IsValid())
             {
-                _playerManager.LocalPlayer?.ControlledEntity?.PopupMessage(Loc.GetString("drag-drop-system-out-of-range-text"));
+                player.PopupMessage(Loc.GetString("drag-drop-system-out-of-range-text"));
             }
 
             _dragDropHelper.EndDrag();
@@ -351,10 +352,10 @@ namespace Content.Client.DragDrop
 
         private void HighlightTargets()
         {
-            if (_dragDropHelper.Dragged == null ||
+            if (_dragDropHelper.Dragged == default ||
-                (!IoCManager.Resolve<IEntityManager>().EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted ||
+                (!EntityManager.EntityExists(_dragDropHelper.Dragged) ? EntityLifeStage.Deleted : EntityManager.GetComponent<MetaDataComponent>(_dragDropHelper.Dragged).EntityLifeStage) >= EntityLifeStage.Deleted ||
-                _dragShadow == null ||
+                _dragShadow == default ||
-                (!IoCManager.Resolve<IEntityManager>().EntityExists(_dragShadow) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_dragShadow).EntityLifeStage) >= EntityLifeStage.Deleted)
+                (!EntityManager.EntityExists(_dragShadow) ? EntityLifeStage.Deleted : EntityManager.GetComponent<MetaDataComponent>(_dragShadow).EntityLifeStage) >= EntityLifeStage.Deleted)
             {
                 Logger.Warning("Programming error. Can't highlight drag and drop targets, not currently " +
                                "dragging anything or dragged entity / shadow was deleted.");
@@ -374,12 +375,12 @@ namespace Content.Client.DragDrop
             var pvsEntities = IoCManager.Resolve<IEntityLookup>().GetEntitiesIntersecting(_eyeManager.CurrentMap, bounds, LookupFlags.Approximate | LookupFlags.IncludeAnchored);
             foreach (var pvsEntity in pvsEntities)
             {
-                if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(pvsEntity, out ISpriteComponent? inRangeSprite) ||
+                if (!EntityManager.TryGetComponent(pvsEntity, out ISpriteComponent? inRangeSprite) ||
                     !inRangeSprite.Visible ||
                     pvsEntity == _dragDropHelper.Dragged) continue;
 
                 // check if it's able to be dropped on by current dragged entity
-                var dropArgs = new DragDropEvent(_dragger!, IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(pvsEntity).Coordinates, _dragDropHelper.Dragged, pvsEntity);
+                var dropArgs = new DragDropEvent(_dragger, EntityManager.GetComponent<TransformComponent>(pvsEntity).Coordinates, _dragDropHelper.Dragged, pvsEntity);
 
                 var valid = ValidDragDrop(dropArgs);
                 if (valid == null) continue;
@@ -422,7 +423,7 @@ namespace Content.Client.DragDrop
 
             bool? valid = null;
 
-            foreach (var comp in IoCManager.Resolve<IEntityManager>().GetComponents<IDragDropOn>(eventArgs.Target))
+            foreach (var comp in EntityManager.GetComponents<IDragDropOn>(eventArgs.Target))
             {
                 if (!comp.CanDragDropOn(eventArgs))
                 {
@@ -440,7 +441,7 @@ namespace Content.Client.DragDrop
             // Need at least one IDraggable to return true or else we can't do shit
             valid = false;
 
-            foreach (var comp in IoCManager.Resolve<IEntityManager>().GetComponents<IDraggable>(eventArgs.User))
+            foreach (var comp in EntityManager.GetComponents<IDraggable>(eventArgs.User))
             {
                 if (!comp.CanDrop(eventArgs)) continue;
                 valid = true;

Content.Client/Examine/ExamineSystem.cs

@@ -10,7 +10,6 @@ using Robust.Client.Graphics;
 using Robust.Client.Player;
 using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
-using Robust.Shared.Containers;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Input.Binding;
 using Robust.Shared.IoC;
@@ -33,8 +32,8 @@ namespace Content.Client.Examine
 
         public const string StyleClassEntityTooltip = "entity-tooltip";
 
-        private IEntity? _examinedEntity;
+        private EntityUid _examinedEntity;
-        private IEntity? _playerEntity;
+        private EntityUid _playerEntity;
         private Popup? _examineTooltipOpen;
         private CancellationTokenSource? _requestCancelTokenSource;
 
@@ -51,8 +50,8 @@ namespace Content.Client.Examine
 
         public override void Update(float frameTime)
         {
-            if (_examineTooltipOpen == null || !_examineTooltipOpen.Visible) return;
+            if (_examineTooltipOpen is not {Visible: true}) return;
-            if (_examinedEntity == null || _playerEntity == null) return;
+            if (!_examinedEntity.Valid || !_playerEntity.Valid) return;
 
             if (!CanExamine(_playerEntity, _examinedEntity))
                 CloseTooltip();
@@ -64,7 +63,7 @@ namespace Content.Client.Examine
             base.Shutdown();
         }
 
-        public override bool CanExamine(IEntity examiner, MapCoordinates target, Ignored? predicate = null)
+        public override bool CanExamine(EntityUid examiner, MapCoordinates target, Ignored? predicate = null)
         {
             var b = _eyeManager.GetWorldViewbounds();
             if (!b.Contains(target.Position))
@@ -73,16 +72,16 @@ namespace Content.Client.Examine
             return base.CanExamine(examiner, target, predicate);
         }
 
-        private bool HandleExamine(ICommonSession? session, EntityCoordinates coords, EntityUid uid)
+        private bool HandleExamine(ICommonSession? session, EntityCoordinates coords, EntityUid entity)
         {
-            if (!uid.IsValid() || !EntityManager.TryGetEntity(uid, out var entity))
+            if (!entity.IsValid() || !EntityManager.EntityExists(entity))
             {
                 return false;
             }
 
-            _playerEntity = _playerManager.LocalPlayer?.ControlledEntity;
+            _playerEntity = _playerManager.LocalPlayer?.ControlledEntity ?? default;
 
-            if (_playerEntity == null || !CanExamine(_playerEntity, entity))
+            if (_playerEntity == default || !CanExamine(_playerEntity, entity))
             {
                 return false;
             }
@@ -104,7 +103,7 @@ namespace Content.Client.Examine
             args.Verbs.Add(verb);
         }
 
-        public async void DoExamine(IEntity entity)
+        public async void DoExamine(EntityUid entity)
         {
             // Close any examine tooltip that might already be opened
             CloseTooltip();

Content.Client/Explosion/ClusterFlashVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Explosion;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Explosion
@@ -17,7 +18,8 @@ namespace Content.Client.Explosion
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent<ISpriteComponent>(out var sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent<ISpriteComponent>(component.Owner, out var sprite))
             {
                 return;
             }

Content.Client/Flash/FlashSystem.cs

@@ -27,7 +27,7 @@ namespace Content.Client.Flash
                 return;
 
             // Yes, this code is awful. I'm just porting it to an entity system so don't blame me.
-            if (_playerManager.LocalPlayer != null && _playerManager.LocalPlayer.Session.AttachedEntityUid != uid)
+            if (_playerManager.LocalPlayer != null && _playerManager.LocalPlayer.Session.AttachedEntity != uid)
             {
                 return;
             }

Content.Client/Fluids/PuddleVisualizer.cs

@@ -10,7 +10,6 @@ using Robust.Shared.Maths;
 using Robust.Shared.Random;
 using Robust.Shared.Serialization.Manager.Attributes;
 
-
 namespace Content.Client.Fluids
 {
     [UsedImplicitly]
@@ -21,7 +20,7 @@ namespace Content.Client.Fluids
         // Whether the underlying solution color should be used
         [DataField("recolor")] public bool Recolor;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
@@ -46,8 +45,9 @@ namespace Content.Client.Fluids
         {
             base.OnChangeData(component);
 
+            var entities = IoCManager.Resolve<IEntityManager>();
             if (component.TryGetData<float>(PuddleVisuals.VolumeScale, out var volumeScale) &&
-                component.Owner.TryGetComponent<SpriteComponent>(out var spriteComponent))
+                entities.TryGetComponent<SpriteComponent>(component.Owner, out var spriteComponent))
             {
                 var cappedScale = Math.Min(1.0f, volumeScale * 0.75f +0.25f);
                 UpdateVisual(component, spriteComponent, cappedScale);

Content.Client/Ghost/GhostSystem.cs

@@ -4,7 +4,6 @@ using Content.Shared.Ghost;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Client.Player;
-using Robust.Client.UserInterface.Controls;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 
@@ -36,7 +35,7 @@ namespace Content.Client.Ghost
 
                 foreach (var ghost in EntityManager.GetAllComponents(typeof(GhostComponent), true))
                 {
-                    if (EntityManager.TryGetComponent(ghost.OwnerUid, out SpriteComponent? sprite))
+                    if (EntityManager.TryGetComponent(ghost.Owner, out SpriteComponent? sprite))
                     {
                         sprite.Visible = value;
                     }
@@ -60,7 +59,7 @@ namespace Content.Client.Ghost
 
         private void OnGhostInit(EntityUid uid, GhostComponent component, ComponentInit args)
         {
-            if (EntityManager.TryGetComponent(component.OwnerUid, out SpriteComponent? sprite))
+            if (EntityManager.TryGetComponent(component.Owner, out SpriteComponent? sprite))
             {
                 sprite.Visible = GhostVisibility;
             }
@@ -101,7 +100,7 @@ namespace Content.Client.Ghost
 
         private void OnGhostWarpsResponse(GhostWarpsResponseEvent msg)
         {
-            var entity = _playerManager.LocalPlayer?.ControlledEntity?.Uid;
+            var entity = _playerManager.LocalPlayer?.ControlledEntity;
 
             if (entity == null ||
                 !EntityManager.TryGetComponent(entity.Value, out GhostComponent? ghost))

Content.Client/Gravity/GravityGeneratorVisualizer.cs

@@ -38,7 +38,7 @@ namespace Content.Client.Gravity
             }
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Hands/HandsGui.xaml.cs

@@ -250,7 +250,7 @@ namespace Content.Client.Hands
         ///     The item being held in this hand.
         /// </summary>
         [ViewVariables]
-        public IEntity? HeldItem { get; }
+        public EntityUid HeldItem { get; }
 
         /// <summary>
         ///     The button in the gui associated with this hand. Assumed to be set by gui shortly after being received from the client HandsComponent.
@@ -258,7 +258,7 @@ namespace Content.Client.Hands
         [ViewVariables]
         public HandButton HandButton { get; set; } = default!;
 
-        public GuiHand(string name, HandLocation handLocation, IEntity? heldItem)
+        public GuiHand(string name, HandLocation handLocation, EntityUid heldItem)
         {
             Name = name;
             HandLocation = handLocation;

Content.Client/Hands/HandsVisualizer.cs

@@ -1,24 +1,22 @@
+using System;
 using Content.Shared.Hands.Components;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Client.ResourceManagement;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
-using Robust.Shared.Maths;
-using System;
-using System.Collections.Generic;
 
 namespace Content.Client.Hands
 {
     [UsedImplicitly]
     public class HandsVisualizer : AppearanceVisualizer
     {
-
         public override void OnChangeData(AppearanceComponent component)
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent<ISpriteComponent>(out var sprite)) return;
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent<ISpriteComponent>(component.Owner, out var sprite)) return;
             if (!component.TryGetData(HandsVisuals.VisualState, out HandsVisualState visualState)) return;
 
             foreach (HandLocation location in Enum.GetValues(typeof(HandLocation)))

Content.Client/Hands/ShowHandItemOverlay.cs

@@ -46,7 +46,7 @@ namespace Content.Client.Hands
             var sys = EntitySystem.Get<HandsSystem>();
             var handEntity = sys.GetActiveHandEntity();
 
-            if (handEntity == null || !_cfg.GetCVar(CCVars.HudHeldItemShow) || !IoCManager.Resolve<IEntityManager>().HasComponent<ISpriteComponent>(handEntity))
+            if (handEntity == default || !_cfg.GetCVar(CCVars.HudHeldItemShow) || !IoCManager.Resolve<IEntityManager>().HasComponent<ISpriteComponent>(handEntity))
                 return;
 
             var screen = args.ScreenHandle;

Content.Client/Hands/Systems/HandsSystem.cs

@@ -56,13 +56,13 @@ namespace Content.Client.Hands
 
         private void HandlePickupAnimation(PickupAnimationMessage msg)
         {
-            if (!EntityManager.TryGetEntity(msg.EntityUid, out var entity))
+            if (!msg.EntityUid.IsValid())
                 return;
 
             if (!_gameTiming.IsFirstTimePredicted)
                 return;
 
-            ReusableAnimations.AnimateEntityPickup(entity, msg.InitialPosition, msg.FinalPosition);
+            ReusableAnimations.AnimateEntityPickup(msg.EntityUid, msg.InitialPosition, msg.FinalPosition);
         }
 
         public HandsGuiState GetGuiState()
@@ -77,10 +77,10 @@ namespace Content.Client.Hands
             return new HandsGuiState(states, hands.ActiveHand);
         }
 
-        public IEntity? GetActiveHandEntity()
+        public EntityUid GetActiveHandEntity()
         {
             if (GetPlayerHandsComponent() is not { ActiveHand: { } active } hands)
-                return null;
+                return default;
 
             return hands.GetHand(active).HeldEntity;
         }
@@ -89,7 +89,7 @@ namespace Content.Client.Hands
         {
             var player = _playerManager.LocalPlayer?.ControlledEntity;
 
-            if (player == null || !IoCManager.Resolve<IEntityManager>().TryGetComponent(player, out HandsComponent? hands))
+            if (player is not {Valid: true} || !EntityManager.TryGetComponent(player.Value, out HandsComponent? hands))
                 return null;
 
             return hands;
@@ -106,7 +106,7 @@ namespace Content.Client.Hands
             var pressedEntity = pressedHand.HeldEntity;
             var activeEntity = activeHand.HeldEntity;
 
-            if (pressedHand == activeHand && activeEntity != null)
+            if (pressedHand == activeHand && activeEntity != default)
             {
                 // use item in hand
                 // it will always be attack_self() in my heart.
@@ -114,21 +114,21 @@ namespace Content.Client.Hands
                 return;
             }
 
-            if (pressedHand != activeHand && pressedEntity == null)
+            if (pressedHand != activeHand && pressedEntity == default)
             {
                 // change active hand
                 RaiseNetworkEvent(new RequestSetHandEvent(handName));
                 return;
             }
 
-            if (pressedHand != activeHand && pressedEntity != null && activeEntity != null)
+            if (pressedHand != activeHand && pressedEntity != default && activeEntity != default)
             {
                 // use active item on held item
                 RaiseNetworkEvent(new ClientInteractUsingInHandMsg(pressedHand.Name));
                 return;
             }
 
-            if (pressedHand != activeHand && pressedEntity != null && activeEntity == null)
+            if (pressedHand != activeHand && pressedEntity != default && activeEntity == default)
             {
                 // use active item on held item
                 RaiseNetworkEvent(new MoveItemFromHandMsg(pressedHand.Name));

Content.Client/HealthOverlay/HealthOverlaySystem.cs

@@ -17,7 +17,7 @@ namespace Content.Client.HealthOverlay
         [Dependency] private readonly IEyeManager _eyeManager = default!;
 
         private readonly Dictionary<EntityUid, HealthOverlayGui> _guis = new();
-        private IEntity? _attachedEntity;
+        private EntityUid _attachedEntity;
         private bool _enabled;
 
         public bool Enabled
@@ -55,7 +55,7 @@ namespace Content.Client.HealthOverlay
             }
 
             _guis.Clear();
-            _attachedEntity = null;
+            _attachedEntity = default;
         }
 
         private void HandlePlayerAttached(PlayerAttachSysMessage message)

Content.Client/HealthOverlay/UI/HealthOverlayGui.cs

@@ -16,8 +16,9 @@ namespace Content.Client.HealthOverlay.UI
     public class HealthOverlayGui : BoxContainer
     {
         [Dependency] private readonly IEyeManager _eyeManager = default!;
+        [Dependency] private readonly IEntityManager _entities = default!;
 
-        public HealthOverlayGui(IEntity entity)
+        public HealthOverlayGui(EntityUid entity)
         {
             IoCManager.InjectDependencies(this);
             IoCManager.Resolve<IUserInterfaceManager>().StateRoot.AddChild(this);
@@ -62,7 +63,7 @@ namespace Content.Client.HealthOverlay.UI
 
         public HealthOverlayBar CritBar { get; }
 
-        public IEntity Entity { get; }
+        public EntityUid Entity { get; }
 
         public void SetVisibility(bool val)
         {
@@ -72,13 +73,13 @@ namespace Content.Client.HealthOverlay.UI
 
         private void MoreFrameUpdate(FrameEventArgs args)
         {
-            if ((!IoCManager.Resolve<IEntityManager>().EntityExists(Entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(Entity).EntityLifeStage) >= EntityLifeStage.Deleted)
+            if ((!_entities.EntityExists(Entity) ? EntityLifeStage.Deleted : _entities.GetComponent<MetaDataComponent>(Entity).EntityLifeStage) >= EntityLifeStage.Deleted)
             {
                 return;
             }
 
-            if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(Entity, out MobStateComponent? mobState) ||
+            if (!_entities.TryGetComponent(Entity, out MobStateComponent? mobState) ||
-                !IoCManager.Resolve<IEntityManager>().TryGetComponent(Entity, out DamageableComponent? damageable))
+                !_entities.TryGetComponent(Entity, out DamageableComponent? damageable))
             {
                 CritBar.Visible = false;
                 HealthBar.Visible = false;
@@ -138,8 +139,8 @@ namespace Content.Client.HealthOverlay.UI
 
             MoreFrameUpdate(args);
 
-            if ((!IoCManager.Resolve<IEntityManager>().EntityExists(Entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(Entity).EntityLifeStage) >= EntityLifeStage.Deleted ||
+            if ((!_entities.EntityExists(Entity) ? EntityLifeStage.Deleted : _entities.GetComponent<MetaDataComponent>(Entity).EntityLifeStage) >= EntityLifeStage.Deleted ||
-                _eyeManager.CurrentMap != IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(Entity).MapID)
+                _eyeManager.CurrentMap != _entities.GetComponent<TransformComponent>(Entity).MapID)
             {
                 Visible = false;
                 return;
@@ -147,7 +148,7 @@ namespace Content.Client.HealthOverlay.UI
 
             Visible = true;
 
-            var screenCoordinates = _eyeManager.CoordinatesToScreen(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(Entity).Coordinates);
+            var screenCoordinates = _eyeManager.CoordinatesToScreen(_entities.GetComponent<TransformComponent>(Entity).Coordinates);
             var playerPosition = UserInterfaceManager.ScreenToUIPosition(screenCoordinates);
             LayoutContainer.SetPosition(this, new Vector2(playerPosition.X - Width / 2, playerPosition.Y - Height - 30.0f));
         }

Content.Client/IconSmoothing/IconSmoothSystem.cs

@@ -51,12 +51,12 @@ namespace Content.Client.IconSmoothing
             // Yes, we updates ALL smoothing entities surrounding us even if they would never smooth with us.
             // This is simpler to implement. If you want to optimize it be my guest.
             var senderEnt = ev.Sender;
-            if (IoCManager.Resolve<IEntityManager>().EntityExists(senderEnt) &&
+            if (EntityManager.EntityExists(senderEnt) &&
-                _mapManager.TryGetGrid(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(senderEnt).GridID, out var grid1) &&
+                _mapManager.TryGetGrid(EntityManager.GetComponent<TransformComponent>(senderEnt).GridID, out var grid1) &&
-                IoCManager.Resolve<IEntityManager>().TryGetComponent(senderEnt, out IconSmoothComponent? iconSmooth)
+                EntityManager.TryGetComponent(senderEnt, out IconSmoothComponent? iconSmooth)
                 && iconSmooth.Running)
             {
-                var coords = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(senderEnt).Coordinates;
+                var coords = EntityManager.GetComponent<TransformComponent>(senderEnt).Coordinates;
 
                 _dirtyEntities.Enqueue(senderEnt);
                 AddValidEntities(grid1.GetInDir(coords, Direction.North));
@@ -130,7 +130,7 @@ namespace Content.Client.IconSmoothing
     /// </summary>
     public sealed class IconSmoothDirtyEvent : EntityEventArgs
     {
-        public IconSmoothDirtyEvent(IEntity sender, (GridId grid, Vector2i pos)? lastPosition, IconSmoothingMode mode)
+        public IconSmoothDirtyEvent(EntityUid sender, (GridId grid, Vector2i pos)? lastPosition, IconSmoothingMode mode)
         {
             LastPosition = lastPosition;
             Mode = mode;
@@ -139,6 +139,6 @@ namespace Content.Client.IconSmoothing
 
         public (GridId grid, Vector2i pos)? LastPosition { get; }
         public IconSmoothingMode Mode { get; }
-        public IEntity Sender { get; }
+        public EntityUid Sender { get; }
     }
 }

Content.Client/Instruments/UI/InstrumentMenu.xaml.cs

@@ -135,11 +135,11 @@ namespace Content.Client.Instruments.UI
             var instrument = _owner.Instrument;
 
             // If either the entity or component are null, return.
-            if (instrumentEnt == null || instrument == null)
+            if (instrumentEnt == default || instrument == default)
                 return false;
 
             // If we're a handheld instrument, we might be in a container. Get it just in case.
-            instrumentEnt.TryGetContainerMan(out var conMan);
+            instrumentEnt.Value.TryGetContainerMan(out var conMan);
 
             var localPlayer = IoCManager.Resolve<IPlayerManager>().LocalPlayer;
 
@@ -151,7 +151,7 @@ namespace Content.Client.Instruments.UI
                                          || conMan.Owner != localPlayer.ControlledEntity))) return false;
 
             // We check that we're in range unobstructed just in case.
-            return localPlayer.InRangeUnobstructed(instrumentEnt,
+            return localPlayer.InRangeUnobstructed(instrumentEnt.Value,
                 predicate: (e) => e == instrumentEnt || e == localPlayer.ControlledEntity);
         }
 

Content.Client/Interactable/InteractionSystem.cs

@@ -9,10 +9,10 @@ namespace Content.Client.Interactable
     {
         public override bool CanAccessViaStorage(EntityUid user, EntityUid target)
         {
-            if (!EntityManager.TryGetEntity(target, out var entity))
+            if (!EntityManager.EntityExists(target))
                 return false;
 
-            if (!entity.TryGetContainer(out var container))
+            if (!target.TryGetContainer(out var container))
                 return false;
 
             if (!EntityManager.TryGetComponent(container.Owner, out ClientStorageComponent storage))

Content.Client/Interactable/UnobstructedExtensions.cs

@@ -15,7 +15,7 @@ namespace Content.Client.Interactable
 
         public static bool InRangeUnobstructed(
             this LocalPlayer origin,
-            IEntity other,
+            EntityUid other,
             float range = InteractionRange,
             CollisionGroup collisionMask = CollisionGroup.Impassable,
             Ignored? predicate = null,
@@ -78,7 +78,7 @@ namespace Content.Client.Interactable
             bool popup = false)
         {
             var originEntity = origin.ControlledEntity;
-            if (originEntity == null)
+            if (originEntity == default)
             {
                 // TODO: Take into account the player's camera position?
                 return false;

Content.Client/Inventory/ClientInventoryComponent.cs

@@ -3,9 +3,7 @@ using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using Content.Client.Clothing;
 using Content.Shared.CharacterAppearance;
-using Content.Shared.Chemistry;
 using Content.Shared.Inventory;
-using Content.Shared.Movement.Components;
 using Content.Shared.Movement.EntitySystems;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
@@ -24,9 +22,9 @@ namespace Content.Client.Inventory
     [ComponentReference(typeof(SharedInventoryComponent))]
     public class ClientInventoryComponent : SharedInventoryComponent
     {
-        private readonly Dictionary<Slots, IEntity> _slots = new();
+        private readonly Dictionary<Slots, EntityUid> _slots = new();
 
-        public IReadOnlyDictionary<Slots, IEntity> AllSlots => _slots;
+        public IReadOnlyDictionary<Slots, EntityUid> AllSlots => _slots;
 
         [ViewVariables] public InventoryInterfaceController InterfaceController { get; private set; } = default!;
 
@@ -78,9 +76,9 @@ namespace Content.Client.Inventory
             }
         }
 
-        public override bool IsEquipped(IEntity item)
+        public override bool IsEquipped(EntityUid item)
         {
-            return item != null && _slots.Values.Any(e => e == item);
+            return item != default && _slots.Values.Any(e => e == item);
         }
 
         public override void HandleComponentState(ComponentState? curState, ComponentState? nextState)
@@ -92,9 +90,9 @@ namespace Content.Client.Inventory
 
             var doneSlots = new HashSet<Slots>();
 
-            foreach (var (slot, entityUid) in state.Entities)
+            foreach (var (slot, entity) in state.Entities)
             {
-                if (!IoCManager.Resolve<IEntityManager>().TryGetEntity(entityUid, out var entity))
+                if (!IoCManager.Resolve<IEntityManager>().EntityExists(entity))
                 {
                     continue;
                 }
@@ -108,9 +106,7 @@ namespace Content.Client.Inventory
 
             if (state.HoverEntity != null)
             {
-                var (slot, (entityUid, fits)) = state.HoverEntity.Value;
+                var (slot, (entity, fits)) = state.HoverEntity.Value;
-                var entity = IoCManager.Resolve<IEntityManager>().GetEntity(entityUid);
-
                 InterfaceController?.HoverInSlot(slot, entity, fits);
             }
 
@@ -126,14 +122,14 @@ namespace Content.Client.Inventory
             EntitySystem.Get<MovementSpeedModifierSystem>().RefreshMovementSpeedModifiers(((IComponent) this).Owner);
         }
 
-        private void _setSlot(Slots slot, IEntity entity)
+        private void _setSlot(Slots slot, EntityUid entity)
         {
             SetSlotVisuals(slot, entity);
 
             InterfaceController?.AddToSlot(slot, entity);
         }
 
-        internal void SetSlotVisuals(Slots slot, IEntity entity)
+        internal void SetSlotVisuals(Slots slot, EntityUid entity)
         {
             if (_sprite == null)
             {
@@ -230,12 +226,12 @@ namespace Content.Client.Inventory
             _playerAttached = true;
         }
 
-        public bool TryGetSlot(Slots slot, [NotNullWhen(true)] out IEntity? item)
+        public bool TryGetSlot(Slots slot, [NotNullWhen(true)] out EntityUid item)
         {
             return _slots.TryGetValue(slot, out item);
         }
 
-        public bool TryFindItemSlots(IEntity item, [NotNullWhen(true)] out Slots? slots)
+        public bool TryFindItemSlots(EntityUid item, [NotNullWhen(true)] out Slots? slots)
         {
             slots = null;
 

Content.Client/Inventory/ClientInventorySystem.cs

@@ -1,5 +1,4 @@
 using Content.Client.HUD;
-using Content.Client.Items.Components;
 using Content.Shared.Input;
 using Content.Shared.Inventory;
 using Content.Shared.Movement.EntitySystems;
@@ -36,7 +35,7 @@ namespace Content.Client.Inventory
         // jesus christ, this is duplicated to server/client, should really just be shared..
         private void OnSlipAttemptEvent(EntityUid uid, ClientInventoryComponent component, SlipAttemptEvent args)
         {
-            if (component.TryGetSlot(EquipmentSlotDefines.Slots.SHOES, out IEntity? shoes))
+            if (component.TryGetSlot(EquipmentSlotDefines.Slots.SHOES, out EntityUid shoes))
             {
                 RaiseLocalEvent(shoes, args, false);
             }
@@ -46,7 +45,7 @@ namespace Content.Client.Inventory
         {
             foreach (var (_, ent) in component.AllSlots)
             {
-                if (ent != null)
+                if (ent != default)
                 {
                     RaiseLocalEvent(ent, args, false);
                 }

Content.Client/Inventory/HumanInventoryInterfaceController.cs

@@ -3,10 +3,8 @@ using System.Linq;
 using Content.Client.HUD;
 using Content.Client.Items.Managers;
 using Content.Client.Items.UI;
-using Content.Shared;
 using Content.Shared.CCVar;
 using JetBrains.Annotations;
-using Robust.Client.ResourceManagement;
 using Robust.Client.UserInterface;
 using Robust.Client.UserInterface.Controls;
 using Robust.Client.UserInterface.CustomControls;
@@ -15,7 +13,6 @@ using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Localization;
 using Robust.Shared.Maths;
-using Robust.Shared.Prototypes;
 using static Content.Shared.Inventory.EquipmentSlotDefines;
 using static Robust.Client.UserInterface.Controls.BoxContainer;
 
@@ -155,7 +152,7 @@ namespace Content.Client.Inventory
             return buttons;
         }
 
-        public override void AddToSlot(Slots slot, IEntity entity)
+        public override void AddToSlot(Slots slot, EntityUid entity)
         {
             base.AddToSlot(slot, entity);
 
@@ -184,7 +181,7 @@ namespace Content.Client.Inventory
             }
         }
 
-        public override void HoverInSlot(Slots slot, IEntity entity, bool fits)
+        public override void HoverInSlot(Slots slot, EntityUid entity, bool fits)
         {
             base.HoverInSlot(slot, entity, fits);
 
@@ -213,7 +210,7 @@ namespace Content.Client.Inventory
         private void ClearButton(ItemSlotButton button, Slots slot)
         {
             button.OnPressed = (e) => AddToInventory(e, slot);
-            _itemSlotManager.SetItemSlot(button, null);
+            _itemSlotManager.SetItemSlot(button, default);
         }
 
         public override void PlayerAttached()

Content.Client/Inventory/InventoryInterfaceController.cs

@@ -46,11 +46,11 @@ namespace Content.Client.Inventory
         /// specified slot, if any. Empty if none.</returns>
         public abstract IEnumerable<ItemSlotButton> GetItemSlotButtons(EquipmentSlotDefines.Slots slot);
 
-        public virtual void AddToSlot(EquipmentSlotDefines.Slots slot, IEntity entity)
+        public virtual void AddToSlot(EquipmentSlotDefines.Slots slot, EntityUid entity)
         {
         }
 
-        public virtual void HoverInSlot(EquipmentSlotDefines.Slots slot, IEntity entity, bool fits)
+        public virtual void HoverInSlot(EquipmentSlotDefines.Slots slot, EntityUid entity, bool fits)
         {
         }
 

Content.Client/Items/Managers/IItemSlotManager.cs

@@ -7,10 +7,10 @@ namespace Content.Client.Items.Managers
 {
     public interface IItemSlotManager
     {
-        bool OnButtonPressed(GUIBoundKeyEventArgs args, IEntity? item);
+        bool OnButtonPressed(GUIBoundKeyEventArgs args, EntityUid item);
-        void UpdateCooldown(ItemSlotButton? cooldownTexture, IEntity? entity);
+        void UpdateCooldown(ItemSlotButton? cooldownTexture, EntityUid entity);
-        bool SetItemSlot(ItemSlotButton button, IEntity? entity);
+        bool SetItemSlot(ItemSlotButton button, EntityUid entity);
-        void HoverInSlot(ItemSlotButton button, IEntity? entity, bool fits);
+        void HoverInSlot(ItemSlotButton button, EntityUid entity, bool fits);
         event Action<EntitySlotHighlightedEventArgs>? EntityHighlightedUpdated;
         bool IsHighlighted(EntityUid uid);
 

Content.Client/Items/Managers/ItemSlotManager.cs

@@ -9,12 +9,8 @@ using Content.Shared.Hands.Components;
 using Content.Shared.Input;
 using Content.Shared.Interaction;
 using Robust.Client.GameObjects;
-using Robust.Client.Graphics;
-using Robust.Client.Input;
-using Robust.Client.Player;
 using Robust.Client.UserInterface;
 using Robust.Shared.GameObjects;
-using Robust.Shared.Input;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
@@ -32,9 +28,9 @@ namespace Content.Client.Items.Managers
 
         public event Action<EntitySlotHighlightedEventArgs>? EntityHighlightedUpdated;
 
-        public bool SetItemSlot(ItemSlotButton button, IEntity? entity)
+        public bool SetItemSlot(ItemSlotButton button, EntityUid entity)
         {
-            if (entity == null)
+            if (entity == default)
             {
                 button.SpriteView.Sprite = null;
                 button.StorageButton.Visible = false;
@@ -42,31 +38,31 @@ namespace Content.Client.Items.Managers
             else
             {
                 ISpriteComponent? sprite;
-                if (IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out HandVirtualItemComponent? virtPull)
+                if (_entityManager.TryGetComponent(entity, out HandVirtualItemComponent? virtPull)
                     && _entityManager.TryGetComponent(virtPull.BlockingEntity, out ISpriteComponent pulledSprite))
                 {
                     sprite = pulledSprite;
                 }
-                else if (!IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out sprite))
+                else if (!_entityManager.TryGetComponent(entity, out sprite))
                 {
                     return false;
                 }
 
                 button.ClearHover();
                 button.SpriteView.Sprite = sprite;
-                button.StorageButton.Visible = IoCManager.Resolve<IEntityManager>().HasComponent<ClientStorageComponent>(entity);
+                button.StorageButton.Visible = _entityManager.HasComponent<ClientStorageComponent>(entity);
             }
 
-            button.Entity = entity ?? default;
+            button.Entity = entity;
 
             // im lazy
             button.UpdateSlotHighlighted();
             return true;
         }
 
-        public bool OnButtonPressed(GUIBoundKeyEventArgs args, IEntity? item)
+        public bool OnButtonPressed(GUIBoundKeyEventArgs args, EntityUid item)
         {
-            if (item == null)
+            if (item == default)
                 return false;
 
             if (args.Function == ContentKeyFunctions.ExamineEntity)
@@ -94,7 +90,7 @@ namespace Content.Client.Items.Managers
             return true;
         }
 
-        public void UpdateCooldown(ItemSlotButton? button, IEntity? entity)
+        public void UpdateCooldown(ItemSlotButton? button, EntityUid entity)
         {
             var cooldownDisplay = button?.CooldownDisplay;
 
@@ -103,9 +99,9 @@ namespace Content.Client.Items.Managers
                 return;
             }
 
-            if (entity == null ||
+            if (entity == default ||
-                (!IoCManager.Resolve<IEntityManager>().EntityExists(entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted ||
+                (!_entityManager.EntityExists(entity) ? EntityLifeStage.Deleted : _entityManager.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted ||
-                !IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out ItemCooldownComponent? cooldown) ||
+                !_entityManager.TryGetComponent(entity, out ItemCooldownComponent? cooldown) ||
                 !cooldown.CooldownStart.HasValue ||
                 !cooldown.CooldownEnd.HasValue)
             {
@@ -124,23 +120,23 @@ namespace Content.Client.Items.Managers
             cooldownDisplay.Visible = ratio > -1f;
         }
 
-        public void HoverInSlot(ItemSlotButton button, IEntity? entity, bool fits)
+        public void HoverInSlot(ItemSlotButton button, EntityUid entity, bool fits)
         {
-            if (entity == null || !button.MouseIsHovering)
+            if (entity == default || !button.MouseIsHovering)
             {
                 button.ClearHover();
                 return;
             }
 
-            if (!IoCManager.Resolve<IEntityManager>().HasComponent<SpriteComponent>(entity))
+            if (!_entityManager.HasComponent<SpriteComponent>(entity))
             {
                 return;
             }
 
             // Set green / red overlay at 50% transparency
             var hoverEntity = _entityManager.SpawnEntity("hoverentity", MapCoordinates.Nullspace);
-            var hoverSprite = IoCManager.Resolve<IEntityManager>().GetComponent<SpriteComponent>(hoverEntity);
+            var hoverSprite = _entityManager.GetComponent<SpriteComponent>(hoverEntity);
-            hoverSprite.CopyFrom(IoCManager.Resolve<IEntityManager>().GetComponent<SpriteComponent>(entity));
+            hoverSprite.CopyFrom(_entityManager.GetComponent<SpriteComponent>(entity));
             hoverSprite.Color = fits ? new Color(0, 255, 0, 127) : new Color(255, 0, 0, 127);
 
             button.HoverSpriteView.Sprite = hoverSprite;

Content.Client/Items/UI/ItemSlotButton.cs

@@ -142,7 +142,7 @@ namespace Content.Client.Items.UI
                 ISpriteComponent? tempQualifier = HoverSpriteView.Sprite;
                 if (tempQualifier != null)
                 {
-                    IoCManager.Resolve<IEntityManager>().DeleteEntity((EntityUid) tempQualifier.Owner);
+                    IoCManager.Resolve<IEntityManager>().DeleteEntity(tempQualifier.Owner);
                 }
 
                 HoverSpriteView.Sprite = null;

Content.Client/Items/UI/ItemStatusPanel.cs

@@ -33,7 +33,7 @@ namespace Content.Client.Items.UI
         private readonly PanelContainer _panel;
 
         [ViewVariables]
-        private IEntity? _entity;
+        private EntityUid _entity;
 
         public ItemStatusPanel(Texture texture, StyleBox.Margin cutout, StyleBox.Margin flat, Label.AlignMode textAlign)
         {
@@ -130,12 +130,12 @@ namespace Content.Client.Items.UI
             UpdateItemName();
         }
 
-        public void Update(IEntity? entity)
+        public void Update(EntityUid entity)
         {
-            if (entity == null)
+            if (entity == default)
             {
                 ClearOldStatus();
-                _entity = null;
+                _entity = default;
                 _panel.Visible = false;
                 return;
             }
@@ -153,17 +153,17 @@ namespace Content.Client.Items.UI
 
         private void UpdateItemName()
         {
-            if (_entity == null)
+            if (_entity == default)
                 return;
 
-            if (IoCManager.Resolve<IEntityManager>().TryGetComponent(_entity, out HandVirtualItemComponent? virtualItem)
+            if (_entityManager.TryGetComponent(_entity, out HandVirtualItemComponent? virtualItem)
-                && _entityManager.TryGetEntity(virtualItem.BlockingEntity, out var blockEnt))
+                && _entityManager.EntityExists(virtualItem.BlockingEntity))
             {
-                _itemNameLabel.Text = IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(blockEnt).EntityName;
+                _itemNameLabel.Text = _entityManager.GetComponent<MetaDataComponent>(virtualItem.BlockingEntity).EntityName;
             }
             else
             {
-                _itemNameLabel.Text = IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(_entity).EntityName;
+                _itemNameLabel.Text = _entityManager.GetComponent<MetaDataComponent>(_entity).EntityName;
             }
         }
 
@@ -185,7 +185,7 @@ namespace Content.Client.Items.UI
 
             ClearOldStatus();
 
-            foreach (var statusComponent in IoCManager.Resolve<IEntityManager>().GetComponents<IItemStatus>(_entity!))
+            foreach (var statusComponent in _entityManager.GetComponents<IItemStatus>(_entity))
             {
                 var control = statusComponent.MakeControl();
                 _statusContents.AddChild(control);
@@ -194,7 +194,7 @@ namespace Content.Client.Items.UI
             }
 
             var collectMsg = new ItemStatusCollectMessage();
-            IoCManager.Resolve<IEntityManager>().EventBus.RaiseLocalEvent(_entity, collectMsg);
+            _entityManager.EventBus.RaiseLocalEvent(_entity, collectMsg);
 
             foreach (var control in collectMsg.Controls)
             {

Content.Client/Kitchen/UI/GrinderMenu.xaml.cs

@@ -76,7 +76,7 @@ namespace Content.Client.Kitchen.UI
                     BeakerContentBox.EjectButton.Disabled = true;
                     ChamberContentBox.EjectButton.Disabled = true;
                     break;
-                case SharedReagentGrinderComponent.ReagentGrinderWorkCompleteMessage doneMessage:
+                case SharedReagentGrinderComponent.ReagentGrinderWorkCompleteMessage:
                     GrindButton.Disabled = false;
                     JuiceButton.Disabled = false;
                     GrindButton.Modulate = Color.White;
@@ -93,9 +93,9 @@ namespace Content.Client.Kitchen.UI
             _chamberVisualContents.Clear();
 
             ChamberContentBox.BoxContents.Clear();
-            foreach (var uid in containedSolids)
+            foreach (var entity in containedSolids)
             {
-                if (!_entityManager.TryGetEntity(uid, out var entity))
+                if (!_entityManager.EntityExists(entity))
                 {
                     return;
                 }
@@ -103,7 +103,7 @@ namespace Content.Client.Kitchen.UI
 
                 var solidItem = ChamberContentBox.BoxContents.AddItem(IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityName, texture);
                 var solidIndex = ChamberContentBox.BoxContents.IndexOf(solidItem);
-                _chamberVisualContents.Add(solidIndex, uid);
+                _chamberVisualContents.Add(solidIndex, entity);
             }
 
             //Refresh beaker contents

Content.Client/Kitchen/UI/MicrowaveBoundUserInterface.cs

@@ -108,24 +108,24 @@ namespace Content.Client.Kitchen.UI
 
             _solids.Clear();
             _menu.IngredientsList.Clear();
-            foreach (var t in containedSolids)
+            foreach (var entity in containedSolids)
             {
-                if (!_entityManager.TryGetEntity(t, out var entity))
+                if (!_entityManager.EntityExists(entity))
                 {
                     return;
                 }
 
-                if ((!IoCManager.Resolve<IEntityManager>().EntityExists(entity) ? EntityLifeStage.Deleted : IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted)
+                if ((!_entityManager.EntityExists(entity) ? EntityLifeStage.Deleted : _entityManager.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted)
                 {
                     continue;
                 }
 
                 Texture? texture;
-                if (IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out IconComponent? iconComponent))
+                if (_entityManager.TryGetComponent(entity, out IconComponent? iconComponent))
                 {
                     texture = iconComponent.Icon?.Default;
                 }
-                else if (IoCManager.Resolve<IEntityManager>().TryGetComponent(entity, out SpriteComponent? spriteComponent))
+                else if (_entityManager.TryGetComponent(entity, out SpriteComponent? spriteComponent))
                 {
                     texture = spriteComponent.Icon?.Default;
                 }
@@ -134,9 +134,9 @@ namespace Content.Client.Kitchen.UI
                     continue;
                 }
 
-                var solidItem = _menu.IngredientsList.AddItem(IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityName, texture);
+                var solidItem = _menu.IngredientsList.AddItem(_entityManager.GetComponent<MetaDataComponent>(entity).EntityName, texture);
                 var solidIndex = _menu.IngredientsList.IndexOf(solidItem);
-                _solids.Add(solidIndex, t);
+                _solids.Add(solidIndex, entity);
             }
         }
     }

Content.Client/Kudzu/KudzuVisualizer.cs

@@ -1,6 +1,7 @@
 using Content.Shared.Kudzu;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Kudzu;
@@ -14,7 +15,8 @@ public class KudzuVisualizer : AppearanceVisualizer
     {
         base.OnChangeData(component);
 
-        if (!component.Owner.TryGetComponent(out SpriteComponent? sprite))
+        var entities = IoCManager.Resolve<IEntityManager>();
+        if (!entities.TryGetComponent(component.Owner, out SpriteComponent? sprite))
         {
             return;
         }

Content.Client/Lathe/Visualizers/AutolatheVisualizer.cs

@@ -48,7 +48,7 @@ namespace Content.Client.Lathe.Visualizers
             return animation;
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             if (!IoCManager.Resolve<IEntityManager>().HasComponent<AnimationPlayerComponent>(entity))
             {

Content.Client/Lathe/Visualizers/ProtolatheVisualizer.cs

@@ -48,7 +48,7 @@ namespace Content.Client.Lathe.Visualizers
             return animation;
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             if (!IoCManager.Resolve<IEntityManager>().HasComponent<AnimationPlayerComponent>(entity))
             {

Content.Client/Light/Components/LightBehaviourComponent.cs

@@ -51,9 +51,9 @@ namespace Content.Client.Light.Components
         [ViewVariables] protected float MaxTime { get; set; }
 
         private float _maxTime = default;
-        private IEntity _parent = default!;
+        private EntityUid _parent = default!;
 
-        public void Initialize(IEntity parent, IRobustRandom random)
+        public void Initialize(EntityUid parent, IRobustRandom random)
         {
             _random = random;
             _parent = parent;
@@ -128,7 +128,7 @@ namespace Content.Client.Light.Components
 
             if (Property == "Enabled") // special case for boolean
             {
-                ApplyProperty(interpolateValue < 0.5f? true : false);
+                ApplyProperty(interpolateValue < 0.5f);
                 return (-1, playingTime);
             }
 
@@ -183,7 +183,7 @@ namespace Content.Client.Light.Components
 
             if (Property == "Enabled") // special case for boolean
             {
-                ApplyProperty(interpolateValue < EndValue? true : false);
+                ApplyProperty(interpolateValue < EndValue);
                 return (-1, playingTime);
             }
 
@@ -258,7 +258,7 @@ namespace Content.Client.Light.Components
                     ApplyProperty(InterpolateLinear(_randomValue3, _randomValue4, interpolateValue));
                     break;
                 case AnimationInterpolationMode.Cubic:
-                    ApplyProperty(InterpolateCubic(_randomValue1!, _randomValue2, _randomValue3, _randomValue4, interpolateValue));
+                    ApplyProperty(InterpolateCubic(_randomValue1, _randomValue2, _randomValue3, _randomValue4, interpolateValue));
                     break;
                 default:
                 case AnimationInterpolationMode.Nearest:

Content.Client/Light/Visualizers/EmergencyLightVisualizer.cs

@@ -1,6 +1,7 @@
 using Content.Shared.Light.Component;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Light.Visualizers
@@ -12,7 +13,8 @@ namespace Content.Client.Light.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out SpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out SpriteComponent? sprite))
                 return;
 
             if (!component.TryGetData(EmergencyLightVisuals.On, out bool on))

Content.Client/Light/Visualizers/ExpendableLightVisualizer.cs

@@ -1,10 +1,10 @@
-using System;
+using Content.Client.Light.Components;
-using Content.Client.Light.Components;
 using Content.Shared.Light.Component;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.Audio;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Player;
 
 namespace Content.Client.Light.Visualizers
@@ -16,9 +16,10 @@ namespace Content.Client.Light.Visualizers
         {
             base.OnChangeData(component);
 
+            var entities = IoCManager.Resolve<IEntityManager>();
             if (component.TryGetData(ExpendableLightVisuals.Behavior, out string lightBehaviourID))
             {
-                if (component.Owner.TryGetComponent<LightBehaviourComponent>(out var lightBehaviour))
+                if (entities.TryGetComponent(component.Owner, out LightBehaviourComponent lightBehaviour))
                 {
                     lightBehaviour.StopLightBehaviour();
 
@@ -26,7 +27,7 @@ namespace Content.Client.Light.Visualizers
                     {
                         lightBehaviour.StartLightBehaviour(lightBehaviourID);
                     }
-                    else if (component.Owner.TryGetComponent<PointLightComponent>(out var light))
+                    else if (entities.TryGetComponent(component.Owner, out PointLightComponent light))
                     {
                         light.Enabled = false;
                     }
@@ -39,7 +40,7 @@ namespace Content.Client.Light.Visualizers
             }
 
             if (component.TryGetData(ExpendableLightVisuals.State, out ExpendableLightState state)
-            && component.Owner.TryGetComponent<ExpendableLightComponent>(out var expendableLight))
+            && entities.TryGetComponent(component.Owner, out ExpendableLightComponent expendableLight))
             {
                 switch (state)
                 {

Content.Client/Light/Visualizers/LightBulbVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Light;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 
 namespace Content.Client.Light.Visualizers
@@ -13,7 +14,8 @@ namespace Content.Client.Light.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent<SpriteComponent>(out var sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out SpriteComponent sprite))
                 return;
 
             // update sprite state

Content.Client/Light/Visualizers/PoweredLightVisualizer.cs

@@ -7,7 +7,6 @@ using Robust.Client.GameObjects;
 using Robust.Shared.Animations;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
-using Robust.Shared.Maths;
 using Robust.Shared.Random;
 using Robust.Shared.Serialization.Manager.Attributes;
 
@@ -28,7 +27,8 @@ namespace Content.Client.Light.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite)) return;
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite)) return;
             if (!component.TryGetData(PoweredLightVisuals.BulbState, out PoweredLightState state)) return;
 
             switch (state)

Content.Client/Lobby/UI/LobbyCharacterPreviewPanel.cs

@@ -23,7 +23,7 @@ namespace Content.Client.Lobby.UI
     public class LobbyCharacterPreviewPanel : Control
     {
         private readonly IClientPreferencesManager _preferencesManager;
-        private IEntity _previewDummy;
+        private EntityUid _previewDummy;
         private readonly Label _summaryLabel;
         private readonly BoxContainer _loaded;
         private readonly Label _unloaded;
@@ -98,11 +98,11 @@ namespace Content.Client.Lobby.UI
             _preferencesManager.OnServerDataLoaded -= UpdateUI;
 
             if (!disposing) return;
-            IoCManager.Resolve<IEntityManager>().DeleteEntity((EntityUid) _previewDummy);
+            IoCManager.Resolve<IEntityManager>().DeleteEntity(_previewDummy);
-            _previewDummy = null!;
+            _previewDummy = default;
         }
 
-        private static SpriteView MakeSpriteView(IEntity entity, Direction direction)
+        private static SpriteView MakeSpriteView(EntityUid entity, Direction direction)
         {
             return new()
             {
@@ -136,7 +136,7 @@ namespace Content.Client.Lobby.UI
             }
         }
 
-        public static void GiveDummyJobClothes(IEntity dummy, HumanoidCharacterProfile profile)
+        public static void GiveDummyJobClothes(EntityUid dummy, HumanoidCharacterProfile profile)
         {
             var protoMan = IoCManager.Resolve<IPrototypeManager>();
 
@@ -144,6 +144,7 @@ namespace Content.Client.Lobby.UI
 
             var highPriorityJob = profile.JobPriorities.FirstOrDefault(p => p.Value == JobPriority.High).Key;
 
+            // ReSharper disable once ConstantNullCoalescingCondition
             var job = protoMan.Index<JobPrototype>(highPriorityJob ?? SharedGameTicker.FallbackOverflowJob);
 
             inventory.ClearAllSlotVisuals();
@@ -160,7 +161,7 @@ namespace Content.Client.Lobby.UI
                     {
                         var item = entityMan.SpawnEntity(itemType, MapCoordinates.Nullspace);
                         inventory.SetSlotVisuals(slot, item);
-                        IoCManager.Resolve<IEntityManager>().DeleteEntity((EntityUid) item);
+                        IoCManager.Resolve<IEntityManager>().DeleteEntity(item);
                     }
                 }
             }

Content.Client/MachineLinking/SignalSwitchVisualizer.cs

@@ -13,7 +13,7 @@ namespace Content.Client.MachineLinking
         [DataField("layer")]
         private int Layer { get; }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 
@@ -27,7 +27,8 @@ namespace Content.Client.MachineLinking
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out SpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out SpriteComponent? sprite))
             {
                 return;
             }

Content.Client/MedicalScanner/UI/MedicalScannerWindow.xaml.cs

@@ -1,17 +1,15 @@
-using System.Text;
 using System.Collections.Generic;
-using System.Linq;
+using System.Text;
-using Robust.Client.UserInterface.Controls;
+using Content.Shared.Damage.Prototypes;
+using Content.Shared.FixedPoint;
+using Robust.Client.AutoGenerated;
 using Robust.Client.UserInterface.CustomControls;
+using Robust.Client.UserInterface.XAML;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Localization;
 using Robust.Shared.Prototypes;
 using static Content.Shared.MedicalScanner.SharedMedicalScannerComponent;
-using Content.Shared.Damage.Prototypes;
-using Content.Shared.FixedPoint;
-using Robust.Client.AutoGenerated;
-using Robust.Client.UserInterface.XAML;
 
 namespace Content.Client.MedicalScanner.UI
 {
@@ -27,9 +25,10 @@ namespace Content.Client.MedicalScanner.UI
         {
             var text = new StringBuilder();
 
+            var entities = IoCManager.Resolve<IEntityManager>();
             if (!state.Entity.HasValue ||
                 !state.HasDamage() ||
-                !IoCManager.Resolve<IEntityManager>().TryGetEntity(state.Entity.Value, out var entity))
+                !entities.EntityExists(state.Entity.Value))
             {
                 Diagnostics.Text = Loc.GetString("medical-scanner-window-no-patient-data-text");
                 ScanButton.Disabled = true;
@@ -37,7 +36,7 @@ namespace Content.Client.MedicalScanner.UI
             }
             else
             {
-                text.Append($"{Loc.GetString("medical-scanner-window-entity-health-text", ("entityName", Name: IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(entity).EntityName))}\n");
+                text.Append($"{Loc.GetString("medical-scanner-window-entity-health-text", ("entityName", Name: entities.GetComponent<MetaDataComponent>(state.Entity.Value).EntityName))}\n");
 
                 var totalDamage = state.DamagePerType.Values.Sum();
 
@@ -46,12 +45,12 @@ namespace Content.Client.MedicalScanner.UI
                 HashSet<string> shownTypes = new();
 
                 // Show the total damage and type breakdown for each damage group.
-                foreach (var (damageGroupID, damageAmount) in state.DamagePerGroup)
+                foreach (var (damageGroupId, damageAmount) in state.DamagePerGroup)
                 {
-                    text.Append($"\n{Loc.GetString("medical-scanner-window-damage-group-text", ("damageGroup", damageGroupID), ("amount", damageAmount))}");
+                    text.Append($"\n{Loc.GetString("medical-scanner-window-damage-group-text", ("damageGroup", damageGroupId), ("amount", damageAmount))}");
 
                     // Show the damage for each type in that group.
-                    var group = IoCManager.Resolve<IPrototypeManager>().Index<DamageGroupPrototype>(damageGroupID);
+                    var group = IoCManager.Resolve<IPrototypeManager>().Index<DamageGroupPrototype>(damageGroupId);
                     foreach (var type in group.DamageTypes)
                     {
                         if (state.DamagePerType.TryGetValue(type, out var typeAmount))

Content.Client/Mining/AsteroidRockVisualizer.cs

@@ -13,7 +13,7 @@ namespace Content.Client.Mining
         [DataField("layer")]
         private int Layer { get; } = 0;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/MobState/Overlays/CritOverlay.cs

@@ -14,6 +14,7 @@ namespace Content.Client.MobState.Overlays
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly IPlayerManager _playerManager = default!;
+        [Dependency] private readonly IEntityManager _entities = default!;
 
         public override OverlaySpace Space => OverlaySpace.WorldSpace;
         private readonly ShaderInstance _gradientCircleShader;
@@ -24,15 +25,14 @@ namespace Content.Client.MobState.Overlays
             _gradientCircleShader = _prototypeManager.Index<ShaderPrototype>("GradientCircleMask").Instance();
         }
 
-        public static bool LocalPlayerHasState(IPlayerManager pm, bool critical, bool dead) {
+        public static bool LocalPlayerHasState(IPlayerManager pm, bool critical, bool dead, IEntityManager? entities = null) {
-            var playerEntity = pm.LocalPlayer?.ControlledEntity;
+            if (pm.LocalPlayer?.ControlledEntity is not {Valid: true} player)
-
-            if (playerEntity == null)
             {
                 return false;
             }
 
-            if (IoCManager.Resolve<IEntityManager>().TryGetComponent<MobStateComponent?>(playerEntity, out var mobState))
+            IoCManager.Resolve(ref entities);
+            if (entities.TryGetComponent<MobStateComponent?>(player, out var mobState))
             {
                 if (critical)
                     if (mobState.IsCritical())
@@ -47,7 +47,7 @@ namespace Content.Client.MobState.Overlays
 
         protected override void Draw(in OverlayDrawArgs args)
         {
-            if (!LocalPlayerHasState(_playerManager, true, false))
+            if (!LocalPlayerHasState(_playerManager, true, false, _entities))
                 return;
 
             var worldHandle = args.WorldHandle;

Content.Client/Morgue/Visualizers/BodyBagVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Labels;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 
 namespace Content.Client.Morgue.Visualizers
 {
@@ -12,7 +13,8 @@ namespace Content.Client.Morgue.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
             {
                 return;
             }

Content.Client/Morgue/Visualizers/CrematoriumVisualizer.cs

@@ -2,6 +2,7 @@
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Morgue.Visualizers
@@ -23,7 +24,11 @@ namespace Content.Client.Morgue.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite)) return;
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
+            {
+                return;
+            }
 
             if (component.TryGetData(MorgueVisuals.Open, out bool open))
             {

Content.Client/Morgue/Visualizers/MorgueVisualizer.cs

@@ -1,6 +1,7 @@
 using Content.Shared.Morgue;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Morgue.Visualizers
@@ -23,7 +24,11 @@ namespace Content.Client.Morgue.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite)) return;
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent? sprite))
+            {
+                return;
+            }
 
             if (component.TryGetData(MorgueVisuals.Open, out bool open))
             {

Content.Client/Movement/Components/ClimbableComponent.cs

@@ -17,7 +17,7 @@ namespace Content.Client.Movement.Components
             var user = eventArgs.User;
             var target = eventArgs.Target;
             var dragged = eventArgs.Dragged;
-            bool Ignored(IEntity entity) => entity == target || entity == user || entity == dragged;
+            bool Ignored(EntityUid entity) => entity == target || entity == user || entity == dragged;
 
             return user.InRangeUnobstructed(target, Range, predicate: Ignored) && user.InRangeUnobstructed(dragged, Range, predicate: Ignored);
         }

Content.Client/NodeContainer/NodeVisualizationOverlay.cs

@@ -5,10 +5,8 @@ using Content.Client.Resources;
 using Robust.Client.Graphics;
 using Robust.Client.Input;
 using Robust.Client.ResourceManagement;
-using Robust.Client.UserInterface.CustomControls;
 using Robust.Shared.Enums;
 using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
 using Robust.Shared.Timing;
@@ -79,14 +77,12 @@ namespace Content.Client.NodeContainer
 
             var mousePos = _inputManager.MouseScreenPosition.Position;
 
-            var entity = _entityManager.GetEntity(node.Entity);
+            var gridId = _entityManager.GetComponent<TransformComponent>(node.Entity).GridID;
-
-            var gridId = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).GridID;
             var grid = _mapManager.GetGrid(gridId);
-            var gridTile = grid.TileIndicesFor(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).Coordinates);
+            var gridTile = grid.TileIndicesFor(_entityManager.GetComponent<TransformComponent>(node.Entity).Coordinates);
 
             var sb = new StringBuilder();
-            sb.Append($"entity: {entity}\n");
+            sb.Append($"entity: {node.Entity}\n");
             sb.Append($"group id: {group.GroupId}\n");
             sb.Append($"node: {node.Name}\n");
             sb.Append($"type: {node.Type}\n");
@@ -120,10 +116,10 @@ namespace Content.Client.NodeContainer
                 if (!_system.Entities.TryGetValue(entity, out var nodeData))
                     return;
 
-                var gridId = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).GridID;
+                var gridId = _entityManager.GetComponent<TransformComponent>(entity).GridID;
                 var grid = _mapManager.GetGrid(gridId);
                 var gridDict = _gridIndex.GetOrNew(gridId);
-                var coords = IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(entity).Coordinates;
+                var coords = _entityManager.GetComponent<TransformComponent>(entity).Coordinates;
 
                 // TODO: This probably shouldn't be capable of returning NaN...
                 if (float.IsNaN(coords.Position.X) || float.IsNaN(coords.Position.Y))

Content.Client/Nutrition/Visualizers/CreamPiedVisualizer.cs

@@ -13,7 +13,7 @@ namespace Content.Client.Nutrition.Visualizers
         [DataField("state")]
         private string? _state;
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
 

Content.Client/Nutrition/Visualizers/DrinkCanVisualizer.cs

@@ -2,6 +2,7 @@ using Content.Shared.Nutrition.Components;
 using JetBrains.Annotations;
 using Robust.Client.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Content.Client.Nutrition.Visualizers
@@ -19,7 +20,8 @@ namespace Content.Client.Nutrition.Visualizers
         {
             base.OnChangeData(component);
 
-            if (!component.Owner.TryGetComponent<ISpriteComponent>(out var sprite))
+            var entities = IoCManager.Resolve<IEntityManager>();
+            if (!entities.TryGetComponent(component.Owner, out ISpriteComponent sprite))
             {
                 return;
             }

Content.Client/PDA/PDAVisualizer.cs

@@ -25,7 +25,7 @@ namespace Content.Client.PDA
             IDLight
         }
 
-        public override void InitializeEntity(IEntity entity)
+        public override void InitializeEntity(EntityUid entity)
         {
             base.InitializeEntity(entity);
             var sprite = IoCManager.Resolve<IEntityManager>().GetComponent<ISpriteComponent>(entity);

Content.Client/Parallax/ParallaxGenerator.cs

@@ -182,7 +182,7 @@ namespace Content.Client.Parallax
                         // Threshold
                         noiseVal = MathF.Max(0, noiseVal - Threshold);
                         noiseVal *= threshVal;
-                        noiseVal = (float) MathF.Pow(noiseVal, powFactor);
+                        noiseVal = MathF.Pow(noiseVal, powFactor);
 
                         // Get colors based on noise values.
                         var srcColor = Color.InterpolateBetween(OuterColor, InnerColor, noiseVal)
@@ -408,7 +408,7 @@ namespace Content.Client.Parallax
                     // Threshold
                     noiseVal = MathF.Max(0, noiseVal - MaskThreshold);
                     noiseVal *= threshVal;
-                    noiseVal = (float) MathF.Pow(noiseVal, powFactor);
+                    noiseVal = MathF.Pow(noiseVal, powFactor);
 
                     var randomThresh = random.NextFloat();
                     if (randomThresh > noiseVal)