diff --git a/Engine.Core/Systems/UniverseEntranceManager.cs b/Engine.Core/Systems/UniverseEntranceManager.cs
index 85f579e..e2919e1 100644
--- a/Engine.Core/Systems/UniverseEntranceManager.cs
+++ b/Engine.Core/Systems/UniverseEntranceManager.cs
@@ -9,9 +9,7 @@ public class UniverseEntranceManager : Internal.BehaviourIndependent
     private static System.Func<IBehaviour, int> GetPriority() => (b) => b.Priority;
 
     private readonly ActiveBehaviourCollectorOrdered<int, IEnterUniverse> enterUniverses = new(GetPriority(), SortByAscendingPriority());
-
-    private readonly List<IEnterUniverse> toCallEnterUniverses = new(32);
-    private readonly List<IExitUniverse> toCallExitUniverses = new(32);
+    private readonly ActiveBehaviourCollectorOrdered<int, IExitUniverse> exitUniverses = new(GetPriority(), SortByAscendingPriority());
 
     protected override void OnEnteredUniverse(IUniverse universe)
     {
@@ -20,54 +18,23 @@ public class UniverseEntranceManager : Internal.BehaviourIndependent
         // event it tries to call OnUniverseObjectRegistered again on the same object, causing a duplicate entry error.
         Debug.Assert.AssertTrue(BehaviourController.Count == 1, $"{nameof(UniverseEntranceManager)} must be in it's own {nameof(IUniverseObject)} with no other {nameof(IBehaviour)}s attached at the moment. Failing to do so might cause instantiation or serialization issues.");
         enterUniverses.Assign(universe);
-
-        foreach (IUniverseObject universeObject in universe)
-            OnUniverseObjectRegistered(universe, new(universeObject));
-
-        universe.OnUniverseObjectRegistered.AddListener(OnUniverseObjectRegistered);
-        universe.OnUniverseObjectUnRegistered.AddListener(OnUniverseObjectUnRegistered);
+        exitUniverses.Assign(universe);
     }
 
     protected override void OnExitedUniverse(IUniverse universe)
     {
         enterUniverses.Unassign();
-
-        foreach (IUniverseObject universeObject in universe)
-            OnUniverseObjectUnRegistered(universe, new(universeObject));
-
-        universe.OnUniverseObjectRegistered.RemoveListener(OnUniverseObjectRegistered);
-        universe.OnUniverseObjectUnRegistered.RemoveListener(OnUniverseObjectUnRegistered);
+        exitUniverses.Unassign();
     }
-
-    private void OnUniverseObjectUnRegistered(IUniverse sender, IUniverse.UniverseObjectUnRegisteredArguments args)
-    {
-        args.UniverseObjectUnregistered.BehaviourController.GetBehavioursInChildren(toCallExitUniverses);
-
-        for (int i = toCallExitUniverses.Count - 1; i >= 0; i--)
-        {
-            IExitUniverse exitUniverse = toCallExitUniverses[i];
-            toCallExitUniverses.RemoveAt(i);
-            exitUniverse.ExitUniverse(Universe);
-        }
-    }
-
-    private void OnUniverseObjectRegistered(IUniverse sender, IUniverse.UniverseObjectRegisteredArguments args)
-    {
-        for (int i = toCallEnterUniverses.Count - 1; i >= 0; i--)
-        {
-            IEnterUniverse enterUniverse = toCallEnterUniverses[i];
-            toCallEnterUniverses.RemoveAt(i);
-            enterUniverse.EnterUniverse(Universe);
-        }
-    }
-
     private void OnEnterUniverseCollected(IBehaviourCollector<IEnterUniverse> sender, IBehaviourCollector<IEnterUniverse>.BehaviourCollectedArguments args)
-    {
-        toCallEnterUniverses.Add(args.BehaviourCollected);
-    }
+        => args.BehaviourCollected.EnterUniverse(Universe);
+
+    private void OnExitUniverseRemoved(IBehaviourCollector<IExitUniverse> sender, IBehaviourCollector<IExitUniverse>.BehaviourRemovedArguments args)
+        => args.BehaviourRemoved.ExitUniverse(Universe);
 
     public UniverseEntranceManager()
     {
         enterUniverses.OnCollected.AddListener(OnEnterUniverseCollected);
+        exitUniverses.OnRemoved.AddListener(OnExitUniverseRemoved);
     }
 }