Deathgasp + last words / succumbing / fake deathgasp as crit actions (#18993)

Content.Server/Mobs/DeathgaspSystem.cs

@@ -0,0 +1,40 @@
+using Content.Server.Chat.Systems;
+using Content.Shared.Mobs;
+using Robust.Shared.Prototypes;
+
+namespace Content.Server.Mobs;
+
+/// <see cref="DeathgaspComponent"/>
+public sealed class DeathgaspSystem: EntitySystem
+{
+    [Dependency] private readonly ChatSystem _chat = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<DeathgaspComponent, MobStateChangedEvent>(OnMobStateChanged);
+    }
+
+    private void OnMobStateChanged(EntityUid uid, DeathgaspComponent component, MobStateChangedEvent args)
+    {
+        // don't deathgasp if they arent going straight from crit to dead
+        if (args.NewMobState != MobState.Dead || args.OldMobState != MobState.Critical)
+            return;
+
+        Deathgasp(uid, component);
+    }
+
+    /// <summary>
+    ///     Causes an entity to perform their deathgasp emote, if they have one.
+    /// </summary>
+    public bool Deathgasp(EntityUid uid, DeathgaspComponent? component = null)
+    {
+        if (!Resolve(uid, ref component, false))
+            return false;
+
+        _chat.TryEmoteWithChat(uid, component.Prototype, ignoreActionBlocker: true);
+
+        return true;
+    }
+}