Add prediction for standing states and mob states (#1937)

Content.Client/GameObjects/Components/Body/BodyManagerComponent.cs

@@ -14,7 +14,7 @@ namespace Content.Client.GameObjects.Components.Body
 {
     [RegisterComponent]
     [ComponentReference(typeof(IDamageableComponent))]
-    [ComponentReference(typeof(IBodyManagerComponent))]
+    [ComponentReference(typeof(ISharedBodyManagerComponent))]
     public class BodyManagerComponent : SharedBodyManagerComponent, IClientDraggable
     {
         [Dependency] private readonly IEntityManager _entityManager = default!;

Content.Client/GameObjects/Components/Mobs/State/CriticalState.cs

@@ -0,0 +1,30 @@
+using Content.Client.GameObjects.EntitySystems;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Client.GameObjects;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Client.GameObjects.Components.Mobs.State
+{
+    public class CriticalState : SharedCriticalState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Critical);
+            }
+
+            EntitySystem.Get<StandingStateSystem>().Down(entity);
+        }
+
+        public override void ExitState(IEntity entity)
+        {
+            EntitySystem.Get<StandingStateSystem>().Standing(entity);
+        }
+
+        public override void UpdateState(IEntity entity) { }
+    }
+}

Content.Client/GameObjects/Components/Mobs/State/DeadState.cs

@@ -0,0 +1,41 @@
+using Content.Client.GameObjects.EntitySystems;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Client.GameObjects;
+using Robust.Shared.GameObjects.Components;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Client.GameObjects.Components.Mobs.State
+{
+    public class DeadState : SharedDeadState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Dead);
+            }
+
+            EntitySystem.Get<StandingStateSystem>().Down(entity);
+
+            if (entity.TryGetComponent(out CollidableComponent collidable))
+            {
+                collidable.CanCollide = false;
+            }
+        }
+
+        public override void ExitState(IEntity entity)
+        {
+            EntitySystem.Get<StandingStateSystem>().Standing(entity);
+
+            if (entity.TryGetComponent(out CollidableComponent collidable))
+            {
+                collidable.CanCollide = true;
+            }
+        }
+
+        public override void UpdateState(IEntity entity) { }
+    }
+}

Content.Client/GameObjects/Components/Mobs/State/MobStateManagerComponent.cs

@@ -0,0 +1,62 @@
+#nullable enable
+using System.Collections.Generic;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Shared.GameObjects;
+
+namespace Content.Client.GameObjects.Components.Mobs.State
+{
+    [RegisterComponent]
+    [ComponentReference(typeof(SharedMobStateManagerComponent))]
+    public class MobStateManagerComponent : SharedMobStateManagerComponent
+    {
+        private readonly Dictionary<DamageState, IMobState> _behavior = new Dictionary<DamageState, IMobState>
+        {
+            {DamageState.Alive, new NormalState()},
+            {DamageState.Critical, new CriticalState()},
+            {DamageState.Dead, new DeadState()}
+        };
+
+        private DamageState _currentDamageState;
+
+        protected override IReadOnlyDictionary<DamageState, IMobState> Behavior => _behavior;
+
+        public override DamageState CurrentDamageState
+        {
+            get => _currentDamageState;
+            protected set
+            {
+                if (_currentDamageState == value)
+                {
+                    return;
+                }
+
+                if (_currentDamageState != DamageState.Invalid)
+                {
+                    CurrentMobState.ExitState(Owner);
+                }
+
+                _currentDamageState = value;
+                CurrentMobState = Behavior[CurrentDamageState];
+                CurrentMobState.EnterState(Owner);
+
+                Dirty();
+            }
+        }
+
+        public override void HandleComponentState(ComponentState? curState, ComponentState? nextState)
+        {
+            base.HandleComponentState(curState, nextState);
+
+            if (!(curState is MobStateManagerComponentState state))
+            {
+                return;
+            }
+
+            _currentDamageState = state.DamageState;
+            CurrentMobState.ExitState(Owner);
+            CurrentMobState = Behavior[CurrentDamageState];
+            CurrentMobState.EnterState(Owner);
+        }
+    }
+}

Content.Client/GameObjects/Components/Mobs/State/NormalState.cs

@@ -0,0 +1,25 @@
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Client.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Client.GameObjects.Components.Mobs.State
+{
+    public class NormalState : SharedNormalState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Alive);
+            }
+
+            UpdateState(entity);
+        }
+
+        public override void ExitState(IEntity entity) { }
+
+        public override void UpdateState(IEntity entity) { }
+    }
+}

Content.Client/GameObjects/EntitySystems/StandingStateSystem.cs

@@ -0,0 +1,50 @@
+using Content.Shared.Audio;
+using Content.Shared.GameObjects.Components.Rotation;
+using Content.Shared.GameObjects.EntitySystems;
+using Robust.Client.GameObjects;
+using Robust.Client.GameObjects.EntitySystems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Client.GameObjects.EntitySystems
+{
+    public class StandingStateSystem : SharedStandingStateSystem
+    {
+        protected override bool OnDown(IEntity entity, bool playSound = true, bool dropItems = true, bool force = false)
+        {
+            if (!entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                return false;
+            }
+
+            var newState = RotationState.Horizontal;
+            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
+
+            if (newState != oldState)
+            {
+                appearance.SetData(RotationVisuals.RotationState, newState);
+            }
+
+            if (playSound)
+            {
+                var file = AudioHelpers.GetRandomFileFromSoundCollection("bodyfall");
+                Get<AudioSystem>().Play(file, entity, AudioHelpers.WithVariation(0.25f));
+            }
+
+            return true;
+        }
+
+        protected override bool OnStand(IEntity entity)
+        {
+            if (!entity.TryGetComponent(out AppearanceComponent appearance)) return false;
+
+            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
+            var newState = RotationState.Vertical;
+
+            if (newState == oldState) return false;
+
+            appearance.SetData(RotationVisuals.RotationState, newState);
+
+            return true;
+        }
+    }
+}

Content.Client/IgnoredComponents.cs

@@ -156,7 +156,6 @@
             "Barotrauma",
             "GasSprayer",
             "GasVapor",
-            "MobStateManager",
             "Metabolism",
             "AiFactionTag",
             "PressureProtection",

Content.Server/AI/WorldState/States/Mobs/NearbyBodiesState.cs

@@ -21,7 +21,7 @@ namespace Content.Server.AI.WorldState.States.Mobs
                 return result;
             }
 
-            foreach (var entity in Visibility.GetEntitiesInRange(Owner.Transform.GridPosition, typeof(IBodyManagerComponent), controller.VisionRadius))
+            foreach (var entity in Visibility.GetEntitiesInRange(Owner.Transform.GridPosition, typeof(ISharedBodyManagerComponent), controller.VisionRadius))
             {
                 if (entity == Owner) continue;
                 result.Add(entity);

Content.Server/GameObjects/Components/Body/BodyManagerComponent.cs

@@ -20,6 +20,7 @@ using Content.Shared.GameObjects.Components.Damage;
 using Content.Shared.GameObjects.Components.Movement;
 using Robust.Server.Interfaces.Player;
 using Robust.Shared.GameObjects;
+using Robust.Shared.GameObjects.Systems;
 using Robust.Shared.Interfaces.GameObjects;
 using Robust.Shared.Interfaces.Reflection;
 using Robust.Shared.IoC;
@@ -38,7 +39,7 @@ namespace Content.Server.GameObjects.Components.Body
     /// </summary>
     [RegisterComponent]
     [ComponentReference(typeof(IDamageableComponent))]
-    [ComponentReference(typeof(IBodyManagerComponent))]
+    [ComponentReference(typeof(ISharedBodyManagerComponent))]
     public class BodyManagerComponent : SharedBodyManagerComponent, IBodyPartContainer, IRelayMoveInput
     {
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
@@ -289,14 +290,14 @@ namespace Content.Server.GameObjects.Components.Body
             if (speedSum <= 0.001f || _activeLegs.Count <= 0)
             {
                 // Case: no way of moving. Fall down.
-                StandingStateHelper.Down(Owner);
+                EntitySystem.Get<StandingStateSystem>().Down(Owner);
                 playerMover.BaseWalkSpeed = 0.8f;
                 playerMover.BaseSprintSpeed = 2.0f;
             }
             else
             {
                 // Case: have at least one leg. Set move speed.
-                StandingStateHelper.Standing(Owner);
+                EntitySystem.Get<StandingStateSystem>().Standing(Owner);
 
                 // Extra legs stack diminishingly.
                 // Final speed = speed sum/(leg count-log4(leg count))

Content.Server/GameObjects/Components/Buckle/BuckleComponent.cs

@@ -3,9 +3,10 @@ using System;
 using System.Diagnostics.CodeAnalysis;
 using Content.Server.GameObjects.Components.GUI;
 using Content.Server.GameObjects.Components.Mobs;
+using Content.Server.GameObjects.Components.Mobs.State;
 using Content.Server.GameObjects.Components.Strap;
+using Content.Server.GameObjects.EntitySystems;
 using Content.Server.Interfaces;
-using Content.Server.Mobs;
 using Content.Server.Utility;
 using Content.Shared.GameObjects.Components.Buckle;
 using Content.Shared.GameObjects.Components.Mobs;
@@ -136,11 +137,11 @@ namespace Content.Server.GameObjects.Components.Buckle
                     ownTransform.WorldRotation = strapTransform.WorldRotation;
                     break;
                 case StrapPosition.Stand:
-                    StandingStateHelper.Standing(Owner);
+                    EntitySystem.Get<StandingStateSystem>().Standing(Owner);
                     ownTransform.WorldRotation = strapTransform.WorldRotation;
                     break;
                 case StrapPosition.Down:
-                    StandingStateHelper.Down(Owner, force: true);
+                    EntitySystem.Get<StandingStateSystem>().Down(Owner, force: true);
                     ownTransform.WorldRotation = Angle.South;
                     break;
             }
@@ -364,11 +365,11 @@ namespace Content.Server.GameObjects.Components.Buckle
 
             if (Owner.TryGetComponent(out StunnableComponent? stunnable) && stunnable.KnockedDown)
             {
-                StandingStateHelper.Down(Owner);
+                EntitySystem.Get<StandingStateSystem>().Down(Owner);
             }
             else
             {
-                StandingStateHelper.Standing(Owner);
+                EntitySystem.Get<StandingStateSystem>().Standing(Owner);
             }
 
             if (Owner.TryGetComponent(out MobStateManagerComponent? stateManager))

Content.Server/GameObjects/Components/Disposal/DisposalHolderComponent.cs

@@ -63,7 +63,7 @@ namespace Content.Server.GameObjects.Components.Disposal
             }
 
             return entity.HasComponent<ItemComponent>() ||
-                   entity.HasComponent<IBodyManagerComponent>();
+                   entity.HasComponent<ISharedBodyManagerComponent>();
         }
 
         public bool TryInsert(IEntity entity)

Content.Server/GameObjects/Components/Disposal/DisposalUnitComponent.cs

@@ -143,7 +143,7 @@ namespace Content.Server.GameObjects.Components.Disposal
             }
 
             if (!entity.HasComponent<ItemComponent>() &&
-                !entity.HasComponent<IBodyManagerComponent>())
+                !entity.HasComponent<ISharedBodyManagerComponent>())
             {
                 return false;
             }

Content.Server/GameObjects/Components/Doors/ServerDoorComponent.cs

@@ -100,7 +100,7 @@ namespace Content.Server.GameObjects.Components.Doors
 
             // Disabled because it makes it suck hard to walk through double doors.
 
-            if (entity.HasComponent<IBodyManagerComponent>())
+            if (entity.HasComponent<ISharedBodyManagerComponent>())
             {
                 if (!entity.TryGetComponent<IMoverComponent>(out var mover)) return;
 

Content.Server/GameObjects/Components/Instruments/InstrumentComponent.cs

@@ -2,6 +2,7 @@
 using System;
 using System.Linq;
 using Content.Server.GameObjects.Components.Mobs;
+using Content.Server.GameObjects.EntitySystems;
 using Content.Server.Interfaces;
 using Content.Server.Mobs;
 using Content.Server.Utility;
@@ -15,6 +16,7 @@ using Robust.Server.Interfaces.Player;
 using Robust.Server.Player;
 using Robust.Shared.Enums;
 using Robust.Shared.GameObjects;
+using Robust.Shared.GameObjects.Systems;
 using Robust.Shared.Interfaces.Network;
 using Robust.Shared.Interfaces.Timing;
 using Robust.Shared.IoC;
@@ -323,7 +325,7 @@ namespace Content.Server.GameObjects.Components.Instruments
                 }
                 else
                 {
-                    StandingStateHelper.DropAllItemsInHands(mob, false);
+                    EntitySystem.Get<StandingStateSystem>().DropAllItemsInHands(mob, false);
                 }
 
                 InstrumentPlayer = null;

Content.Server/GameObjects/Components/Medical/HealingComponent.cs

@@ -32,7 +32,7 @@ namespace Content.Server.GameObjects.Components.Medical
                 return;
             }
 
-            if (!eventArgs.Target.TryGetComponent(out IBodyManagerComponent body))
+            if (!eventArgs.Target.TryGetComponent(out ISharedBodyManagerComponent body))
             {
                 return;
             }

Content.Server/GameObjects/Components/Mobs/MobStateManager.cs

@@ -1,513 +0,0 @@
-using System.Collections.Generic;
-using Content.Server.GameObjects.Components.Body;
-using Content.Server.GameObjects.Components.Damage;
-using Content.Server.Mobs;
-using Content.Shared.GameObjects.Components.Damage;
-using Content.Shared.GameObjects.Components.Mobs;
-using Content.Shared.GameObjects.EntitySystems;
-using Robust.Server.GameObjects;
-using Robust.Shared.GameObjects;
-using Robust.Shared.GameObjects.Components;
-using Robust.Shared.Interfaces.GameObjects;
-
-namespace Content.Server.GameObjects.Components.Mobs
-{
-    /// <summary>
-    ///     When attacked to an <see cref="IDamageableComponent"/>, this component will handle critical and death behaviors
-    ///     for mobs.
-    ///     Additionally, it handles sending effects to clients (such as blur effect for unconsciousness) and managing the
-    ///     health HUD.
-    /// </summary>
-    [RegisterComponent]
-    internal class MobStateManagerComponent : Component, IOnHealthChangedBehavior, IActionBlocker
-    {
-        private readonly Dictionary<DamageState, IMobState> _behavior = new Dictionary<DamageState, IMobState>
-        {
-            {DamageState.Alive, new NormalState()},
-            {DamageState.Critical, new CriticalState()},
-            {DamageState.Dead, new DeadState()}
-        };
-
-        public override string Name => "MobStateManager";
-
-        private DamageState _currentDamageState;
-
-        public IMobState CurrentMobState { get; private set; } = new NormalState();
-
-        bool IActionBlocker.CanInteract()
-        {
-            return CurrentMobState.CanInteract();
-        }
-
-        bool IActionBlocker.CanMove()
-        {
-            return CurrentMobState.CanMove();
-        }
-
-        bool IActionBlocker.CanUse()
-        {
-            return CurrentMobState.CanUse();
-        }
-
-        bool IActionBlocker.CanThrow()
-        {
-            return CurrentMobState.CanThrow();
-        }
-
-        bool IActionBlocker.CanSpeak()
-        {
-            return CurrentMobState.CanSpeak();
-        }
-
-        bool IActionBlocker.CanDrop()
-        {
-            return CurrentMobState.CanDrop();
-        }
-
-        bool IActionBlocker.CanPickup()
-        {
-            return CurrentMobState.CanPickup();
-        }
-
-        bool IActionBlocker.CanEmote()
-        {
-            return CurrentMobState.CanEmote();
-        }
-
-        bool IActionBlocker.CanAttack()
-        {
-            return CurrentMobState.CanAttack();
-        }
-
-        bool IActionBlocker.CanEquip()
-        {
-            return CurrentMobState.CanEquip();
-        }
-
-        bool IActionBlocker.CanUnequip()
-        {
-            return CurrentMobState.CanUnequip();
-        }
-
-        bool IActionBlocker.CanChangeDirection()
-        {
-            return CurrentMobState.CanChangeDirection();
-        }
-
-        public void OnHealthChanged(HealthChangedEventArgs e)
-        {
-            if (e.Damageable.CurrentDamageState != _currentDamageState)
-            {
-                _currentDamageState = e.Damageable.CurrentDamageState;
-                CurrentMobState.ExitState(Owner);
-                CurrentMobState = _behavior[_currentDamageState];
-                CurrentMobState.EnterState(Owner);
-            }
-
-            CurrentMobState.UpdateState(Owner);
-        }
-
-        public override void Initialize()
-        {
-            base.Initialize();
-
-            _currentDamageState = DamageState.Alive;
-            CurrentMobState = _behavior[_currentDamageState];
-            CurrentMobState.EnterState(Owner);
-            CurrentMobState.UpdateState(Owner);
-        }
-
-        public override void OnRemove()
-        {
-            // TODO: Might want to add an OnRemove() to IMobState since those are where these components are being used
-            base.OnRemove();
-
-            if (Owner.TryGetComponent(out ServerStatusEffectsComponent status))
-            {
-                status.RemoveStatusEffect(StatusEffect.Health);
-            }
-
-            if (Owner.TryGetComponent(out ServerOverlayEffectsComponent overlay))
-            {
-                overlay.ClearOverlays();
-            }
-        }
-    }
-
-    /// <summary>
-    ///     Defines the blocking effects of an associated <see cref="DamageState"/>
-    ///     (i.e. Normal, Critical, Dead) and what effects to apply upon entering or
-    ///     exiting the state.
-    /// </summary>
-    public interface IMobState : IActionBlocker
-    {
-        /// <summary>
-        ///     Called when this state is entered.
-        /// </summary>
-        void EnterState(IEntity entity);
-
-        /// <summary>
-        ///     Called when this state is left for a different state.
-        /// </summary>
-        void ExitState(IEntity entity);
-
-        /// <summary>
-        ///     Called when this state is updated.
-        /// </summary>
-        void UpdateState(IEntity entity);
-    }
-
-    /// <summary>
-    ///     The standard state an entity is in; no negative effects.
-    /// </summary>
-    public struct NormalState : IMobState
-    {
-        public void EnterState(IEntity entity)
-        {
-            if (entity.TryGetComponent(out AppearanceComponent appearance))
-            {
-                appearance.SetData(DamageStateVisuals.State, DamageState.Alive);
-            }
-
-            UpdateState(entity);
-        }
-
-        public void ExitState(IEntity entity) { }
-
-        public void UpdateState(IEntity entity)
-        {
-            if (!entity.TryGetComponent(out ServerStatusEffectsComponent status))
-            {
-                return;
-            }
-
-            if (!entity.TryGetComponent(out IDamageableComponent damageable))
-            {
-                status.ChangeStatusEffectIcon(StatusEffect.Health,
-                    "/Textures/Interface/StatusEffects/Human/human0.png");
-                return;
-            }
-
-            // TODO
-            switch (damageable)
-            {
-                case RuinableComponent ruinable:
-                {
-                    if (ruinable.DeadThreshold == null)
-                    {
-                        break;
-                    }
-
-                    var modifier = (int) (ruinable.TotalDamage / (ruinable.DeadThreshold / 7f));
-
-                    status.ChangeStatusEffectIcon(StatusEffect.Health,
-                        "/Textures/Interface/StatusEffects/Human/human" + modifier + ".png");
-
-                    break;
-                }
-                case BodyManagerComponent body:
-                {
-                    if (body.CriticalThreshold == null)
-                    {
-                        return;
-                    }
-
-                    var modifier = (int) (body.TotalDamage / (body.CriticalThreshold / 7f));
-
-                    status.ChangeStatusEffectIcon(StatusEffect.Health,
-                        "/Textures/Interface/StatusEffects/Human/human" + modifier + ".png");
-
-                    break;
-                }
-                default:
-                {
-                    status.ChangeStatusEffectIcon(StatusEffect.Health,
-                        "/Textures/Interface/StatusEffects/Human/human0.png");
-                    break;
-                }
-            }
-        }
-
-        bool IActionBlocker.CanInteract()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanMove()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanUse()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanThrow()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanSpeak()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanDrop()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanPickup()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanEmote()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanAttack()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanEquip()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanUnequip()
-        {
-            return true;
-        }
-
-        bool IActionBlocker.CanChangeDirection()
-        {
-            return true;
-        }
-    }
-
-    /// <summary>
-    ///     A state in which an entity is disabled from acting due to sufficient damage (considered unconscious).
-    /// </summary>
-    public struct CriticalState : IMobState
-    {
-        public void EnterState(IEntity entity)
-        {
-            if (entity.TryGetComponent(out AppearanceComponent appearance))
-            {
-                appearance.SetData(DamageStateVisuals.State, DamageState.Critical);
-            }
-
-            if (entity.TryGetComponent(out ServerStatusEffectsComponent status))
-            {
-                status.ChangeStatusEffectIcon(StatusEffect.Health,
-                    "/Textures/Interface/StatusEffects/Human/humancrit-0.png"); //Todo: combine humancrit-0 and humancrit-1 into a gif and display it
-            }
-
-            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
-            {
-                overlay.AddOverlay(SharedOverlayID.GradientCircleMaskOverlay);
-            }
-
-            if (entity.TryGetComponent(out StunnableComponent stun))
-            {
-                stun.CancelAll();
-            }
-
-            StandingStateHelper.Down(entity);
-        }
-
-        public void ExitState(IEntity entity)
-        {
-            StandingStateHelper.Standing(entity);
-
-            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
-            {
-                overlay.ClearOverlays();
-            }
-        }
-
-        public void UpdateState(IEntity entity)
-        {
-        }
-
-        bool IActionBlocker.CanInteract()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanMove()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanUse()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanThrow()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanSpeak()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanDrop()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanPickup()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanEmote()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanAttack()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanEquip()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanUnequip()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanChangeDirection()
-        {
-            return false;
-        }
-    }
-
-    /// <summary>
-    ///     The state representing a dead entity; allows for ghosting.
-    /// </summary>
-    public struct DeadState : IMobState
-    {
-        public void EnterState(IEntity entity)
-        {
-            if (entity.TryGetComponent(out AppearanceComponent appearance))
-            {
-                appearance.SetData(DamageStateVisuals.State, DamageState.Dead);
-            }
-
-            if (entity.TryGetComponent(out ServerStatusEffectsComponent status))
-            {
-                status.ChangeStatusEffectIcon(StatusEffect.Health,
-                    "/Textures/Interface/StatusEffects/Human/humandead.png");
-            }
-
-            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlayComponent))
-            {
-                overlayComponent.AddOverlay(SharedOverlayID.CircleMaskOverlay);
-            }
-
-            if (entity.TryGetComponent(out StunnableComponent stun))
-            {
-                stun.CancelAll();
-            }
-
-            StandingStateHelper.Down(entity);
-
-            if (entity.TryGetComponent(out CollidableComponent collidable))
-            {
-                collidable.CanCollide = false;
-            }
-        }
-
-        public void ExitState(IEntity entity)
-        {
-            StandingStateHelper.Standing(entity);
-
-            if (entity.TryGetComponent(out CollidableComponent collidable))
-            {
-                collidable.CanCollide = true;
-            }
-
-            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
-            {
-                overlay.ClearOverlays();
-            }
-        }
-
-        public void UpdateState(IEntity entity)
-        {
-        }
-
-        bool IActionBlocker.CanInteract()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanMove()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanUse()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanThrow()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanSpeak()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanDrop()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanPickup()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanEmote()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanAttack()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanEquip()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanUnequip()
-        {
-            return false;
-        }
-
-        bool IActionBlocker.CanChangeDirection()
-        {
-            return false;
-        }
-    }
-}

Content.Server/GameObjects/Components/Mobs/State/CriticalState.cs

@@ -0,0 +1,51 @@
+using Content.Server.GameObjects.EntitySystems;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Server.GameObjects;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Server.GameObjects.Components.Mobs.State
+{
+    public class CriticalState : SharedCriticalState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Critical);
+            }
+
+            if (entity.TryGetComponent(out ServerStatusEffectsComponent status))
+            {
+                status.ChangeStatusEffectIcon(StatusEffect.Health,
+                    "/Textures/Interface/StatusEffects/Human/humancrit-0.png"); //Todo: combine humancrit-0 and humancrit-1 into a gif and display it
+            }
+
+            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
+            {
+                overlay.AddOverlay(SharedOverlayID.GradientCircleMaskOverlay);
+            }
+
+            if (entity.TryGetComponent(out StunnableComponent stun))
+            {
+                stun.CancelAll();
+            }
+
+            EntitySystem.Get<StandingStateSystem>().Down(entity);
+        }
+
+        public override void ExitState(IEntity entity)
+        {
+            EntitySystem.Get<StandingStateSystem>().Standing(entity);
+
+            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
+            {
+                overlay.ClearOverlays();
+            }
+        }
+
+        public override void UpdateState(IEntity entity) { }
+    }
+}

Content.Server/GameObjects/Components/Mobs/State/DeadState.cs

@@ -0,0 +1,62 @@
+using Content.Server.GameObjects.EntitySystems;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Server.GameObjects;
+using Robust.Shared.GameObjects.Components;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Server.GameObjects.Components.Mobs.State
+{
+    public class DeadState : SharedDeadState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Dead);
+            }
+
+            if (entity.TryGetComponent(out ServerStatusEffectsComponent status))
+            {
+                status.ChangeStatusEffectIcon(StatusEffect.Health,
+                    "/Textures/Interface/StatusEffects/Human/humandead.png");
+            }
+
+            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlayComponent))
+            {
+                overlayComponent.AddOverlay(SharedOverlayID.CircleMaskOverlay);
+            }
+
+            if (entity.TryGetComponent(out StunnableComponent stun))
+            {
+                stun.CancelAll();
+            }
+
+            EntitySystem.Get<StandingStateSystem>().Down(entity);
+
+            if (entity.TryGetComponent(out CollidableComponent collidable))
+            {
+                collidable.CanCollide = false;
+            }
+        }
+
+        public override void ExitState(IEntity entity)
+        {
+            EntitySystem.Get<StandingStateSystem>().Standing(entity);
+
+            if (entity.TryGetComponent(out CollidableComponent collidable))
+            {
+                collidable.CanCollide = true;
+            }
+
+            if (entity.TryGetComponent(out ServerOverlayEffectsComponent overlay))
+            {
+                overlay.ClearOverlays();
+            }
+        }
+
+        public override void UpdateState(IEntity entity) { }
+    }
+}

Content.Server/GameObjects/Components/Mobs/State/MobStateManager.cs

@@ -0,0 +1,70 @@
+using System.Collections.Generic;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.GameObjects.Components.Mobs.State
+{
+    [RegisterComponent]
+    [ComponentReference(typeof(SharedMobStateManagerComponent))]
+    public class MobStateManagerComponent : SharedMobStateManagerComponent
+    {
+        private readonly Dictionary<DamageState, IMobState> _behavior = new Dictionary<DamageState, IMobState>
+        {
+            {DamageState.Alive, new NormalState()},
+            {DamageState.Critical, new CriticalState()},
+            {DamageState.Dead, new DeadState()}
+        };
+
+        private DamageState _currentDamageState;
+
+        protected override IReadOnlyDictionary<DamageState, IMobState> Behavior => _behavior;
+
+        public override IMobState CurrentMobState { get; protected set; }
+
+        public override DamageState CurrentDamageState
+        {
+            get => _currentDamageState;
+            protected set
+            {
+                if (_currentDamageState == value)
+                {
+                    return;
+                }
+
+                if (_currentDamageState != DamageState.Invalid)
+                {
+                    CurrentMobState.ExitState(Owner);
+                }
+
+                _currentDamageState = value;
+                CurrentMobState = Behavior[CurrentDamageState];
+                CurrentMobState.EnterState(Owner);
+
+                Dirty();
+            }
+        }
+
+        public override void OnRemove()
+        {
+            // TODO: Might want to add an OnRemove() to IMobState since those are where these components are being used
+            base.OnRemove();
+
+            if (Owner.TryGetComponent(out ServerStatusEffectsComponent status))
+            {
+                status.RemoveStatusEffect(StatusEffect.Health);
+            }
+
+            if (Owner.TryGetComponent(out ServerOverlayEffectsComponent overlay))
+            {
+                overlay.ClearOverlays();
+            }
+        }
+
+        public override ComponentState GetComponentState()
+        {
+            return new MobStateManagerComponentState(CurrentDamageState);
+        }
+    }
+}

Content.Server/GameObjects/Components/Mobs/State/NormalState.cs

@@ -0,0 +1,79 @@
+using Content.Server.GameObjects.Components.Body;
+using Content.Server.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.Components.Mobs;
+using Content.Shared.GameObjects.Components.Mobs.State;
+using Robust.Server.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Server.GameObjects.Components.Mobs.State
+{
+    public class NormalState : SharedNormalState
+    {
+        public override void EnterState(IEntity entity)
+        {
+            if (entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                appearance.SetData(DamageStateVisuals.State, DamageState.Alive);
+            }
+
+            UpdateState(entity);
+        }
+
+        public override void ExitState(IEntity entity) { }
+
+        public override void UpdateState(IEntity entity)
+        {
+            if (!entity.TryGetComponent(out ServerStatusEffectsComponent status))
+            {
+                return;
+            }
+
+            if (!entity.TryGetComponent(out IDamageableComponent damageable))
+            {
+                status.ChangeStatusEffectIcon(StatusEffect.Health,
+                    "/Textures/Interface/StatusEffects/Human/human0.png");
+                return;
+            }
+
+            // TODO
+            switch (damageable)
+            {
+                case RuinableComponent ruinable:
+                {
+                    if (ruinable.DeadThreshold == null)
+                    {
+                        break;
+                    }
+
+                    var modifier = (int) (ruinable.TotalDamage / (ruinable.DeadThreshold / 7f));
+
+                    status.ChangeStatusEffectIcon(StatusEffect.Health,
+                        "/Textures/Interface/StatusEffects/Human/human" + modifier + ".png");
+
+                    break;
+                }
+                case BodyManagerComponent body:
+                {
+                    if (body.CriticalThreshold == null)
+                    {
+                        return;
+                    }
+
+                    var modifier = (int) (body.TotalDamage / (body.CriticalThreshold / 7f));
+
+                    status.ChangeStatusEffectIcon(StatusEffect.Health,
+                        "/Textures/Interface/StatusEffects/Human/human" + modifier + ".png");
+
+                    break;
+                }
+                default:
+                {
+                    status.ChangeStatusEffectIcon(StatusEffect.Health,
+                        "/Textures/Interface/StatusEffects/Human/human0.png");
+                    break;
+                }
+            }
+        }
+    }
+}

Content.Server/GameObjects/Components/Mobs/StunnableComponent.cs

@@ -1,7 +1,8 @@
-using Content.Server.Mobs;
+using Content.Server.GameObjects.EntitySystems;
 using Content.Shared.GameObjects.Components.Mobs;
 using Content.Shared.GameObjects.Components.Movement;
 using Robust.Shared.GameObjects;
+using Robust.Shared.GameObjects.Systems;
 using Robust.Shared.Interfaces.Timing;
 using Robust.Shared.IoC;
 using Robust.Shared.Timers;
@@ -16,7 +17,7 @@ namespace Content.Server.GameObjects.Components.Mobs
 
         protected override void OnKnockdown()
         {
-            StandingStateHelper.Down(Owner);
+            EntitySystem.Get<StandingStateSystem>().Down(Owner);
         }
 
         public void CancelAll()
@@ -33,7 +34,7 @@ namespace Content.Server.GameObjects.Components.Mobs
 
             if (KnockedDown)
             {
-                StandingStateHelper.Standing(Owner);
+                EntitySystem.Get<StandingStateSystem>().Standing(Owner);
             }
 
             KnockdownTimer = 0f;
@@ -58,7 +59,7 @@ namespace Content.Server.GameObjects.Components.Mobs
 
                 if (KnockdownTimer <= 0f)
                 {
-                    StandingStateHelper.Standing(Owner);
+                    EntitySystem.Get<StandingStateSystem>().Standing(Owner);
 
                     KnockdownTimer = 0f;
                     Dirty();

Content.Server/GameObjects/Components/Recycling/RecyclerComponent.cs

@@ -69,7 +69,7 @@ namespace Content.Server.GameObjects.Components.Recycling
 
         private bool CanGib(IEntity entity)
         {
-            return entity.HasComponent<IBodyManagerComponent>() && !_safe && Powered;
+            return entity.HasComponent<ISharedBodyManagerComponent>() && !_safe && Powered;
         }
 
         private bool CanRecycle(IEntity entity, [MaybeNullWhen(false)] out ConstructionPrototype prototype)

Content.Server/GameObjects/EntitySystems/StandingStateSystem.cs

@@ -0,0 +1,65 @@
+using Content.Server.Interfaces.GameObjects.Components.Items;
+using Content.Shared.Audio;
+using Content.Shared.GameObjects.Components.Rotation;
+using Content.Shared.GameObjects.EntitySystems;
+using JetBrains.Annotations;
+using Robust.Server.GameObjects;
+using Robust.Server.GameObjects.EntitySystems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Server.GameObjects.EntitySystems
+{
+    [UsedImplicitly]
+    public class StandingStateSystem : SharedStandingStateSystem
+    {
+        protected override bool OnDown(IEntity entity, bool playSound = true, bool dropItems = true, bool force = false)
+        {
+            if (!entity.TryGetComponent(out AppearanceComponent appearance))
+            {
+                return false;
+            }
+
+            var newState = RotationState.Horizontal;
+            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
+
+            if (newState != oldState)
+            {
+                appearance.SetData(RotationVisuals.RotationState, newState);
+            }
+
+            if (playSound)
+            {
+                var file = AudioHelpers.GetRandomFileFromSoundCollection("bodyfall");
+                Get<AudioSystem>().PlayFromEntity(file, entity, AudioHelpers.WithVariation(0.25f));
+            }
+
+            return true;
+        }
+
+        protected override bool OnStand(IEntity entity)
+        {
+            if (!entity.TryGetComponent(out AppearanceComponent appearance)) return false;
+
+            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
+            var newState = RotationState.Vertical;
+
+            if (newState == oldState) return false;
+
+            appearance.SetData(RotationVisuals.RotationState, newState);
+
+            return true;
+        }
+
+        public override void DropAllItemsInHands(IEntity entity, bool doMobChecks = true)
+        {
+            base.DropAllItemsInHands(entity, doMobChecks);
+
+            if (!entity.TryGetComponent(out IHandsComponent hands)) return;
+
+            foreach (var heldItem in hands.GetAllHeldItems())
+            {
+                hands.Drop(heldItem.Owner, doMobChecks);
+            }
+        }
+    }
+}

Content.Server/GameObjects/EntitySystems/StationEvents/RadiationPulseSystem.cs

@@ -34,7 +34,7 @@ namespace Content.Server.GameObjects.EntitySystems.StationEvents
         public override void Initialize()
         {
             base.Initialize();
-            _speciesQuery = new TypeEntityQuery(typeof(IBodyManagerComponent));
+            _speciesQuery = new TypeEntityQuery(typeof(ISharedBodyManagerComponent));
         }
 
         public override void Update(float frameTime)

Content.Server/Mobs/StandingStateHelper.cs

@@ -1,84 +0,0 @@
-using Content.Server.Interfaces.GameObjects.Components.Items;
-using Content.Shared.Audio;
-using Content.Shared.GameObjects.Components.Rotation;
-using Content.Shared.GameObjects.EntitySystems;
-using Robust.Server.GameObjects;
-using Robust.Server.GameObjects.EntitySystems;
-using Robust.Shared.Interfaces.GameObjects;
-using Robust.Shared.IoC;
-
-namespace Content.Server.Mobs
-{
-    public static class StandingStateHelper
-    {
-        /// <summary>
-        ///     Set's the mob standing state to down.
-        /// </summary>
-        /// <param name="entity">The mob in question</param>
-        /// <param name="playSound">Whether to play a sound when falling down or not</param>
-        /// <param name="dropItems">Whether to make the mob drop all the items on his hands</param>
-        /// <param name="force">Whether or not to check if the entity can fall.</param>
-        /// <returns>False if the mob was already downed or couldn't set the state</returns>
-        public static bool Down(IEntity entity, bool playSound = true, bool dropItems = true, bool force = false)
-        {
-            if (dropItems)
-            {
-                DropAllItemsInHands(entity, false);
-            }
-
-            if (!force && !EffectBlockerSystem.CanFall(entity))
-            {
-                return false;
-            }
-
-            if (!entity.TryGetComponent(out AppearanceComponent appearance))
-            {
-                return false;
-            }
-
-            var newState = RotationState.Horizontal;
-            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
-
-            if (newState != oldState)
-            {
-                appearance.SetData(RotationVisuals.RotationState, newState);
-            }
-
-            if (playSound)
-            {
-                IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<AudioSystem>()
-                    .PlayFromEntity(AudioHelpers.GetRandomFileFromSoundCollection("bodyfall"), entity, AudioHelpers.WithVariation(0.25f));
-            }
-
-            return true;
-        }
-
-        /// <summary>
-        ///     Sets the mob's standing state to standing.
-        /// </summary>
-        /// <param name="entity">The mob in question.</param>
-        /// <returns>False if the mob was already standing or couldn't set the state</returns>
-        public static bool Standing(IEntity entity)
-        {
-            if (!entity.TryGetComponent(out AppearanceComponent appearance)) return false;
-            appearance.TryGetData<RotationState>(RotationVisuals.RotationState, out var oldState);
-            var newState = RotationState.Vertical;
-            if (newState == oldState)
-                return false;
-
-            appearance.SetData(RotationVisuals.RotationState, newState);
-
-            return true;
-        }
-
-        public static void DropAllItemsInHands(IEntity entity, bool doMobChecks = true)
-        {
-            if (!entity.TryGetComponent(out IHandsComponent hands)) return;
-
-            foreach (var heldItem in hands.GetAllHeldItems())
-            {
-                hands.Drop(heldItem.Owner, doMobChecks);
-            }
-        }
-    }
-}

Content.Shared/GameObjects/Components/Body/ISharedBodyManagerComponent.cs

@@ -1,9 +1,8 @@
 using Content.Shared.GameObjects.Components.Damage;
-using Robust.Shared.Interfaces.GameObjects;
 
 namespace Content.Shared.GameObjects.Components.Body
 {
-    public interface IBodyManagerComponent : IDamageableComponent
+    public interface ISharedBodyManagerComponent : IDamageableComponent
     {
     }
 }

Content.Shared/GameObjects/Components/Body/SharedBodyManagerComponent.cs

@@ -5,7 +5,7 @@ using Robust.Shared.Serialization;
 
 namespace Content.Shared.GameObjects.Components.Body
 {
-    public abstract class SharedBodyManagerComponent : DamageableComponent, IBodyManagerComponent
+    public abstract class SharedBodyManagerComponent : DamageableComponent, ISharedBodyManagerComponent
     {
         public override string Name => "BodyManager";
 

Content.Shared/GameObjects/Components/Damage/DamageState.cs

@@ -16,6 +16,7 @@ namespace Content.Shared.GameObjects.Components.Damage
     [Serializable, NetSerializable]
     public enum DamageState
     {
+        Invalid = 0,
         Alive,
         Critical,
         Dead

Content.Shared/GameObjects/Components/Damage/IDamageableComponent.cs

@@ -143,8 +143,8 @@ namespace Content.Shared.GameObjects.Components.Damage
                 _ => throw new ArgumentOutOfRangeException()
             };
 
-            ChangeDamage(DamageType.Piercing, damage, false, null);
+            ChangeDamage(DamageType.Piercing, damage, false);
-            ChangeDamage(DamageType.Heat, damage, false, null);
+            ChangeDamage(DamageType.Heat, damage, false);
         }
     }
 

Content.Shared/GameObjects/Components/Mobs/State/IMobState.cs

@@ -0,0 +1,29 @@
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.EntitySystems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.GameObjects.Components.Mobs.State
+{
+    /// <summary>
+    ///     Defines the blocking effects of an associated <see cref="DamageState"/>
+    ///     (i.e. Normal, Critical, Dead) and what effects to apply upon entering or
+    ///     exiting the state.
+    /// </summary>
+    public interface IMobState : IActionBlocker
+    {
+        /// <summary>
+        ///     Called when this state is entered.
+        /// </summary>
+        void EnterState(IEntity entity);
+
+        /// <summary>
+        ///     Called when this state is left for a different state.
+        /// </summary>
+        void ExitState(IEntity entity);
+
+        /// <summary>
+        ///     Called when this state is updated.
+        /// </summary>
+        void UpdateState(IEntity entity);
+    }
+}

Content.Shared/GameObjects/Components/Mobs/State/SharedCriticalState.cs

@@ -0,0 +1,76 @@
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.GameObjects.Components.Mobs.State
+{
+    /// <summary>
+    ///     A state in which an entity is disabled from acting due to sufficient damage (considered unconscious).
+    /// </summary>
+    public abstract class SharedCriticalState : IMobState
+    {
+        public abstract void EnterState(IEntity entity);
+
+        public abstract void ExitState(IEntity entity);
+
+        public abstract void UpdateState(IEntity entity);
+
+        public bool CanInteract()
+        {
+            return false;
+        }
+
+        public bool CanMove()
+        {
+            return false;
+        }
+
+        public bool CanUse()
+        {
+            return false;
+        }
+
+        public bool CanThrow()
+        {
+            return false;
+        }
+
+        public bool CanSpeak()
+        {
+            return false;
+        }
+
+        public bool CanDrop()
+        {
+            return false;
+        }
+
+        public bool CanPickup()
+        {
+            return false;
+        }
+
+        public bool CanEmote()
+        {
+            return false;
+        }
+
+        public bool CanAttack()
+        {
+            return false;
+        }
+
+        public bool CanEquip()
+        {
+            return false;
+        }
+
+        public bool CanUnequip()
+        {
+            return false;
+        }
+
+        public bool CanChangeDirection()
+        {
+            return false;
+        }
+    }
+}

Content.Shared/GameObjects/Components/Mobs/State/SharedDeadState.cs

@@ -0,0 +1,73 @@
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.GameObjects.Components.Mobs.State
+{
+    public abstract class SharedDeadState : IMobState
+    {
+        public abstract void EnterState(IEntity entity);
+
+        public abstract void ExitState(IEntity entity);
+
+        public abstract void UpdateState(IEntity entity);
+
+        public bool CanInteract()
+        {
+            return false;
+        }
+
+        public bool CanMove()
+        {
+            return false;
+        }
+
+        public bool CanUse()
+        {
+            return false;
+        }
+
+        public bool CanThrow()
+        {
+            return false;
+        }
+
+        public bool CanSpeak()
+        {
+            return false;
+        }
+
+        public bool CanDrop()
+        {
+            return false;
+        }
+
+        public bool CanPickup()
+        {
+            return false;
+        }
+
+        public bool CanEmote()
+        {
+            return false;
+        }
+
+        public bool CanAttack()
+        {
+            return false;
+        }
+
+        public bool CanEquip()
+        {
+            return false;
+        }
+
+        public bool CanUnequip()
+        {
+            return false;
+        }
+
+        public bool CanChangeDirection()
+        {
+            return false;
+        }
+    }
+}

Content.Shared/GameObjects/Components/Mobs/State/SharedMobStateManagerComponent.cs

@@ -0,0 +1,128 @@
+using System;
+using System.Collections.Generic;
+using Content.Shared.GameObjects.Components.Damage;
+using Content.Shared.GameObjects.EntitySystems;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.GameObjects.Components.Mobs.State
+{
+    /// <summary>
+    ///     When attacked to an <see cref="IDamageableComponent"/>, this component will
+    ///     handle critical and death behaviors for mobs.
+    ///     Additionally, it handles sending effects to clients
+    ///     (such as blur effect for unconsciousness) and managing the health HUD.
+    /// </summary>
+    public abstract class SharedMobStateManagerComponent : Component, IOnHealthChangedBehavior, IActionBlocker
+    {
+        public override string Name => "MobStateManager";
+
+        public override uint? NetID => ContentNetIDs.MOB_STATE_MANAGER;
+
+        protected abstract IReadOnlyDictionary<DamageState, IMobState> Behavior { get; }
+
+        public virtual IMobState CurrentMobState { get; protected set; }
+
+        public virtual DamageState CurrentDamageState { get; protected set; }
+
+        public override void OnAdd()
+        {
+            base.OnAdd();
+
+            CurrentDamageState = DamageState.Alive;
+        }
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            CurrentMobState = Behavior[CurrentDamageState];
+            CurrentMobState.EnterState(Owner);
+            CurrentMobState.UpdateState(Owner);
+        }
+
+        bool IActionBlocker.CanInteract()
+        {
+            return CurrentMobState.CanInteract();
+        }
+
+        bool IActionBlocker.CanMove()
+        {
+            return CurrentMobState.CanMove();
+        }
+
+        bool IActionBlocker.CanUse()
+        {
+            return CurrentMobState.CanUse();
+        }
+
+        bool IActionBlocker.CanThrow()
+        {
+            return CurrentMobState.CanThrow();
+        }
+
+        bool IActionBlocker.CanSpeak()
+        {
+            return CurrentMobState.CanSpeak();
+        }
+
+        bool IActionBlocker.CanDrop()
+        {
+            return CurrentMobState.CanDrop();
+        }
+
+        bool IActionBlocker.CanPickup()
+        {
+            return CurrentMobState.CanPickup();
+        }
+
+        bool IActionBlocker.CanEmote()
+        {
+            return CurrentMobState.CanEmote();
+        }
+
+        bool IActionBlocker.CanAttack()
+        {
+            return CurrentMobState.CanAttack();
+        }
+
+        bool IActionBlocker.CanEquip()
+        {
+            return CurrentMobState.CanEquip();
+        }
+
+        bool IActionBlocker.CanUnequip()
+        {
+            return CurrentMobState.CanUnequip();
+        }
+
+        bool IActionBlocker.CanChangeDirection()
+        {
+            return CurrentMobState.CanChangeDirection();
+        }
+
+        public void OnHealthChanged(HealthChangedEventArgs e)
+        {
+            if (e.Damageable.CurrentDamageState != CurrentDamageState)
+            {
+                CurrentDamageState = e.Damageable.CurrentDamageState;
+                CurrentMobState.ExitState(Owner);
+                CurrentMobState = Behavior[CurrentDamageState];
+                CurrentMobState.EnterState(Owner);
+            }
+
+            CurrentMobState.UpdateState(Owner);
+        }
+    }
+
+    [Serializable, NetSerializable]
+    public class MobStateManagerComponentState : ComponentState
+    {
+        public readonly DamageState DamageState;
+
+        public MobStateManagerComponentState(DamageState damageState) : base(ContentNetIDs.MOB_STATE_MANAGER)
+        {
+            DamageState = damageState;
+        }
+    }
+}

Content.Shared/GameObjects/Components/Mobs/State/SharedNormalState.cs

@@ -0,0 +1,76 @@
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.GameObjects.Components.Mobs.State
+{
+    /// <summary>
+    ///     The standard state an entity is in; no negative effects.
+    /// </summary>
+    public abstract class SharedNormalState : IMobState
+    {
+        public abstract void EnterState(IEntity entity);
+
+        public abstract void ExitState(IEntity entity);
+
+        public abstract void UpdateState(IEntity entity);
+
+        public bool CanInteract()
+        {
+            return true;
+        }
+
+        public bool CanMove()
+        {
+            return true;
+        }
+
+        public bool CanUse()
+        {
+            return true;
+        }
+
+        public bool CanThrow()
+        {
+            return true;
+        }
+
+        public bool CanSpeak()
+        {
+            return true;
+        }
+
+        public bool CanDrop()
+        {
+            return true;
+        }
+
+        public bool CanPickup()
+        {
+            return true;
+        }
+
+        public bool CanEmote()
+        {
+            return true;
+        }
+
+        public bool CanAttack()
+        {
+            return true;
+        }
+
+        public bool CanEquip()
+        {
+            return true;
+        }
+
+        public bool CanUnequip()
+        {
+            return true;
+        }
+
+        public bool CanChangeDirection()
+        {
+            return true;
+        }
+    }
+}

Content.Shared/GameObjects/Components/Movement/SharedPlayerInputMoverComponent.cs

@@ -270,7 +270,7 @@ namespace Content.Shared.GameObjects.Components.Movement
         bool ICollideSpecial.PreventCollide(IPhysBody collidedWith)
         {
             // Don't collide with other mobs
-            return collidedWith.Entity.HasComponent<IBodyManagerComponent>();
+            return collidedWith.Entity.HasComponent<ISharedBodyManagerComponent>();
         }
 
         [Serializable, NetSerializable]

Content.Shared/GameObjects/Components/Rotation/SharedRotationComponent.cs

@@ -1,5 +1,4 @@
 using System;
-using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization;
 
 namespace Content.Shared.GameObjects.Components.Rotation

Content.Shared/GameObjects/ContentNetIDs.cs

@@ -72,6 +72,8 @@
         public const uint HANDCUFFS = 1066;
         public const uint BATTERY_BARREL = 1067;
         public const uint SUSPICION_ROLE = 1068;
+        public const uint ROTATION = 1069;
+        public const uint MOB_STATE_MANAGER = 1070;
 
         // Net IDs for integration tests.
         public const uint PREDICTION_TEST = 10001;

Content.Shared/GameObjects/EntitySystems/SharedStandingStateSystem.cs

@@ -0,0 +1,50 @@
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.GameObjects.EntitySystems
+{
+    public abstract class SharedStandingStateSystem : EntitySystem
+    {
+        protected abstract bool OnDown(IEntity entity, bool playSound = true, bool dropItems = true,
+            bool force = false);
+
+        protected abstract bool OnStand(IEntity entity);
+
+        /// <summary>
+        ///     Set's the mob standing state to down.
+        /// </summary>
+        /// <param name="entity">The mob in question</param>
+        /// <param name="playSound">Whether to play a sound when falling down or not</param>
+        /// <param name="dropItems">Whether to make the mob drop all the items on his hands</param>
+        /// <param name="force">Whether or not to check if the entity can fall.</param>
+        /// <returns>False if the mob was already downed or couldn't set the state</returns>
+        public bool Down(IEntity entity, bool playSound = true, bool dropItems = true, bool force = false)
+        {
+            if (dropItems)
+            {
+                DropAllItemsInHands(entity, false);
+            }
+
+            if (!force && !EffectBlockerSystem.CanFall(entity))
+            {
+                return false;
+            }
+
+            return OnDown(entity, playSound, dropItems, force);
+        }
+
+        /// <summary>
+        ///     Sets the mob's standing state to standing.
+        /// </summary>
+        /// <param name="entity">The mob in question.</param>
+        /// <returns>False if the mob was already standing or couldn't set the state</returns>
+        public bool Standing(IEntity entity)
+        {
+            return OnStand(entity);
+        }
+
+        public virtual void DropAllItemsInHands(IEntity entity, bool doMobChecks = true)
+        {
+        }
+    }
+}