diff --git a/Robust.Client/Player/PlayerSession.cs b/Robust.Client/Player/PlayerSession.cs
index 3a0aed2636..ebc752c587 100644
--- a/Robust.Client/Player/PlayerSession.cs
+++ b/Robust.Client/Player/PlayerSession.cs
@@ -17,7 +17,7 @@ namespace Robust.Client.Player
         }
 
         /// <inheritdoc />
-        public EntityUid AttachedEntity { get; set; }
+        public EntityUid? AttachedEntity { get; set; }
 
         /// <inheritdoc />
         public NetUserId UserId { get; }
diff --git a/Robust.Server/GameObjects/EntitySystems/ActorSystem.cs b/Robust.Server/GameObjects/EntitySystems/ActorSystem.cs
index db2ba0378a..9723b44a4c 100644
--- a/Robust.Server/GameObjects/EntitySystems/ActorSystem.cs
+++ b/Robust.Server/GameObjects/EntitySystems/ActorSystem.cs
@@ -115,7 +115,7 @@ namespace Robust.Server.GameObjects
         public bool Detach(IPlayerSession player)
         {
             var uid = player.AttachedEntity;
-            return uid == default || Detach(uid);
+            return uid == null || Detach(uid.Value);
         }
 
         private void OnActorShutdown(EntityUid entity, ActorComponent component, ComponentShutdown args)
diff --git a/Robust.Server/GameStates/PVSSystem.cs b/Robust.Server/GameStates/PVSSystem.cs
index fb79b5b858..2f58d16141 100644
--- a/Robust.Server/GameStates/PVSSystem.cs
+++ b/Robust.Server/GameStates/PVSSystem.cs
@@ -579,8 +579,8 @@ internal partial class PVSSystem : EntitySystem
         if (session.Status != SessionStatus.InGame)
             return viewers;
 
-        if (session.AttachedEntity != EntityUid.Invalid)
-            viewers.Add(session.AttachedEntity);
+        if (session.AttachedEntity != null)
+            viewers.Add(session.AttachedEntity.Value);
 
         // This is awful, but we're not gonna add the list of view subscriptions to common session.
         if (session is IPlayerSession playerSession)
diff --git a/Robust.Server/Player/PlayerSession.cs b/Robust.Server/Player/PlayerSession.cs
index e2142c7823..7ac1310cb0 100644
--- a/Robust.Server/Player/PlayerSession.cs
+++ b/Robust.Server/Player/PlayerSession.cs
@@ -43,7 +43,7 @@ namespace Robust.Server.Player
         [ViewVariables] public INetChannel ConnectedClient { get; }
 
         /// <inheritdoc />
-        [ViewVariables] public EntityUid AttachedEntity { get; set; }
+        [ViewVariables] public EntityUid? AttachedEntity { get; set; }
 
         private SessionStatus _status = SessionStatus.Connecting;
 
@@ -151,7 +151,7 @@ namespace Robust.Server.Player
             }
 #endif
 
-            if (!EntitySystem.Get<ActorSystem>().Detach(AttachedEntity))
+            if (!EntitySystem.Get<ActorSystem>().Detach(AttachedEntity.Value))
             {
                 Logger.Warning($"Couldn't detach player \"{this}\" from entity \"{AttachedEntity}\"! Is it missing an ActorComponent?");
             }
@@ -177,9 +177,9 @@ namespace Robust.Server.Player
 
         private void SetAttachedEntityName()
         {
-            if (Name != null && AttachedEntity != default)
+            if (Name != null && AttachedEntity != null)
             {
-                IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(AttachedEntity).EntityName = Name;
+                IoCManager.Resolve<IEntityManager>().GetComponent<MetaDataComponent>(AttachedEntity.Value).EntityName = Name;
             }
         }
 
diff --git a/Robust.Shared/Containers/ContainerHelpers.cs b/Robust.Shared/Containers/ContainerHelpers.cs
index ac0c64f96f..1b0b15d6e9 100644
--- a/Robust.Shared/Containers/ContainerHelpers.cs
+++ b/Robust.Shared/Containers/ContainerHelpers.cs
@@ -23,8 +23,7 @@ namespace Robust.Shared.Containers
         public static bool IsInContainer(this EntityUid entity)
         {
             var entMan = IoCManager.Resolve<IEntityManager>();
-            DebugTools.AssertNotNull(entity);
-            DebugTools.Assert(!((!entMan.EntityExists(entity) ? EntityLifeStage.Deleted : entMan.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted));
+            DebugTools.Assert(entMan.EntityExists(entity));
 
             // Notice the recursion starts at the Owner of the passed in entity, this
             // allows containers inside containers (toolboxes in lockers).
@@ -46,8 +45,7 @@ namespace Robust.Shared.Containers
         public static bool TryGetContainerMan(this EntityUid entity, [NotNullWhen(true)] out IContainerManager? manager)
         {
             var entMan = IoCManager.Resolve<IEntityManager>();
-            DebugTools.AssertNotNull(entity);
-            DebugTools.Assert(!((!entMan.EntityExists(entity) ? EntityLifeStage.Deleted : entMan.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted));
+            DebugTools.Assert(entMan.EntityExists(entity));
 
             var parentTransform = entMan.GetComponent<TransformComponent>(entity).Parent;
             if (parentTransform != null && TryGetManagerComp(parentTransform.Owner, out manager) && manager.ContainsEntity(entity))
@@ -66,8 +64,7 @@ namespace Robust.Shared.Containers
         public static bool TryGetContainer(this EntityUid entity, [NotNullWhen(true)] out IContainer? container)
         {
             var entMan = IoCManager.Resolve<IEntityManager>();
-            DebugTools.AssertNotNull(entity);
-            DebugTools.Assert(!((!entMan.EntityExists(entity) ? EntityLifeStage.Deleted : entMan.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted));
+            DebugTools.Assert(entMan.EntityExists(entity));
 
             if (TryGetContainerMan(entity, out var manager))
                 return manager.TryGetContainer(entity, out container);
@@ -86,8 +83,7 @@ namespace Robust.Shared.Containers
         public static bool TryRemoveFromContainer(this EntityUid entity, bool force, out bool wasInContainer)
         {
             var entMan = IoCManager.Resolve<IEntityManager>();
-            DebugTools.AssertNotNull(entity);
-            DebugTools.Assert(!((!entMan.EntityExists(entity) ? EntityLifeStage.Deleted : entMan.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted));
+            DebugTools.Assert(entMan.EntityExists(entity));
 
             if (TryGetContainer(entity, out var container))
             {
@@ -175,8 +171,7 @@ namespace Robust.Shared.Containers
         private static bool TryGetManagerComp(this EntityUid entity, [NotNullWhen(true)] out IContainerManager? manager)
         {
             var entMan = IoCManager.Resolve<IEntityManager>();
-            DebugTools.AssertNotNull(entity);
-            DebugTools.Assert(!((!entMan.EntityExists(entity) ? EntityLifeStage.Deleted : entMan.GetComponent<MetaDataComponent>(entity).EntityLifeStage) >= EntityLifeStage.Deleted));
+            DebugTools.Assert(entMan.EntityExists(entity));
 
             if (entMan.TryGetComponent(entity, out manager))
                 return true;
@@ -190,9 +185,6 @@ namespace Robust.Shared.Containers
 
         public static bool IsInSameOrNoContainer(this EntityUid user, EntityUid other)
         {
-            DebugTools.AssertNotNull(user);
-            DebugTools.AssertNotNull(other);
-
             var isUserContained = TryGetContainer(user, out var userContainer);
             var isOtherContained = TryGetContainer(other, out var otherContainer);
 
@@ -208,9 +200,6 @@ namespace Robust.Shared.Containers
 
         public static bool IsInSameOrParentContainer(this EntityUid user, EntityUid other)
         {
-            DebugTools.AssertNotNull(user);
-            DebugTools.AssertNotNull(other);
-
             var isUserContained = TryGetContainer(user, out var userContainer);
             var isOtherContained = TryGetContainer(other, out var otherContainer);
 
diff --git a/Robust.Shared/Player/Filter.cs b/Robust.Shared/Player/Filter.cs
index faeeab85e4..182b034660 100644
--- a/Robust.Shared/Player/Filter.cs
+++ b/Robust.Shared/Player/Filter.cs
@@ -156,7 +156,7 @@ namespace Robust.Shared.Player
         {
             return AddWhere(session =>
                 session.AttachedEntity != null &&
-                position.InRange(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(session.AttachedEntity).MapPosition, range), playerMan);
+                position.InRange(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(session.AttachedEntity.Value).MapPosition, range), playerMan);
         }
 
         /// <summary>
@@ -165,7 +165,7 @@ namespace Robust.Shared.Player
         public Filter RemoveByVisibility(uint flag)
         {
             return RemoveWhere(session =>
-                session.AttachedEntity == default
+                session.AttachedEntity == null
                 || !IoCManager.Resolve<IEntityManager>().TryGetComponent(session.AttachedEntity, out SharedEyeComponent? eye)
                 || (eye.VisibilityMask & flag) == 0);
         }
@@ -204,8 +204,8 @@ namespace Robust.Shared.Player
         public Filter RemoveInRange(MapCoordinates position, float range)
         {
             return RemoveWhere(session =>
-                session.AttachedEntity != default &&
-                position.InRange(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(session.AttachedEntity).MapPosition, range));
+                session.AttachedEntity != null &&
+                position.InRange(IoCManager.Resolve<IEntityManager>().GetComponent<TransformComponent>(session.AttachedEntity.Value).MapPosition, range));
         }
 
         /// <summary>
diff --git a/Robust.Shared/Players/ICommonSession.cs b/Robust.Shared/Players/ICommonSession.cs
index 8f3062d9d3..b7fff9e3a8 100644
--- a/Robust.Shared/Players/ICommonSession.cs
+++ b/Robust.Shared/Players/ICommonSession.cs
@@ -18,7 +18,7 @@ namespace Robust.Shared.Players
         /// <summary>
         /// Entity UID that this session is represented by in the world, if any.
         /// </summary>
-        EntityUid AttachedEntity { get; }
+        EntityUid? AttachedEntity { get; }
 
         /// <summary>
         /// The UID of this session.