diff --git a/src/Arch/Core/CommandBuffer/SparseSet.cs b/src/Arch/Core/CommandBuffer/SparseSet.cs
index e176b1ef..18436704 100644
--- a/src/Arch/Core/CommandBuffer/SparseSet.cs
+++ b/src/Arch/Core/CommandBuffer/SparseSet.cs
@@ -169,7 +169,7 @@ public ref T Get<T>(int index)
     /// </summary>
     public void Clear()
     {
-        for (var index = 0; index < Size; index++)
+        for (var index = 0; index < Entities.Length; index++)
         {
             Entities[index] = -1;
         }
diff --git a/src/Arch/Core/CommandBuffer/StructuralSparseSet.cs b/src/Arch/Core/CommandBuffer/StructuralSparseSet.cs
index 8db25aec..7f872de7 100644
--- a/src/Arch/Core/CommandBuffer/StructuralSparseSet.cs
+++ b/src/Arch/Core/CommandBuffer/StructuralSparseSet.cs
@@ -102,7 +102,7 @@ public bool Contains(int index)
     /// </summary>
     public void Clear()
     {
-        for (var index = 0; index < Size; index++)
+        for (var index = 0; index < Entities.Length; index++)
         {
             Entities[index] = -1;
         }
diff --git a/src/Arch/Core/Extensions/EntityExtensions.cs b/src/Arch/Core/Extensions/EntityExtensions.cs
index 47c9ad3e..e6e3dad7 100644
--- a/src/Arch/Core/Extensions/EntityExtensions.cs
+++ b/src/Arch/Core/Extensions/EntityExtensions.cs
@@ -167,6 +167,20 @@ public static ref T TryGetRef<T>(this in Entity entity, out bool exists)
         return ref world.TryGetRef<T>(entity, out exists);
     }
 
+    /// <summary>
+    ///    Ensures the existance of an component on an <see cref="Entity"/>.
+    /// </summary>
+    /// <typeparam name="T">The component type.</typeparam>
+    /// <param name="entity">The <see cref="Entity"/>.</param>
+    /// <param name="cmp">The component value used if its being added.</param>
+    /// <returns>A reference to the component.</returns>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static ref T AddOrGet<T>(this in Entity entity, T cmp = default)
+    {
+        var world = World.Worlds[entity.WorldId];
+        return ref world.AddOrGet(entity, cmp);
+    }
+
     /// <summary>
     ///     Adds an new component to the <see cref="Entity"/> and moves it to the new <see cref="Archetype"/>.
     /// </summary>
diff --git a/src/Arch/Core/World.cs b/src/Arch/Core/World.cs
index 78572210..d006fcf0 100644
--- a/src/Arch/Core/World.cs
+++ b/src/Arch/Core/World.cs
@@ -929,13 +929,15 @@ public ref T Get<T>(Entity entity)
     public bool TryGet<T>(Entity entity, out T component)
     {
         component = default;
-        if (!Has<T>(entity))
+
+        var slot = EntityInfo.GetSlot(entity.Id);
+        var archetype = EntityInfo.GetArchetype(entity.Id);
+
+        if (!archetype.Has<T>())
         {
             return false;
         }
 
-        var slot = EntityInfo.GetSlot(entity.Id);
-        var archetype = EntityInfo.GetArchetype(entity.Id);
         component = archetype.Get<T>(ref slot);
         return true;
     }
@@ -950,16 +952,37 @@ public bool TryGet<T>(Entity entity, out T component)
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public ref T TryGetRef<T>(Entity entity, out bool exists)
     {
-        if (!(exists = Has<T>(entity)))
+        var slot = EntityInfo.GetSlot(entity.Id);
+        var archetype = EntityInfo.GetArchetype(entity.Id);
+
+        if (!(exists = archetype.Has<T>()))
         {
             return ref Unsafe.NullRef<T>();
         }
 
-        var slot = EntityInfo.GetSlot(entity.Id);
-        var archetype = EntityInfo.GetArchetype(entity.Id);
         return ref archetype.Get<T>(ref slot);
     }
 
+    /// <summary>
+    ///     Ensures the existence of an component on an <see cref="Entity"/>.
+    /// </summary>
+    /// <typeparam name="T">The component type.</typeparam>
+    /// <param name="entity">The <see cref="Entity"/>.</param>
+    /// <param name="cmp">The component value used if its being added.</param>
+    /// <returns>A reference to the component.</returns>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public ref T AddOrGet<T>(Entity entity, T cmp = default)
+    {
+        ref var component = ref TryGetRef<T>(entity, out var exists);
+        if (exists)
+        {
+            return ref component;
+        }
+
+        Add(entity, cmp);
+        return ref Get<T>(entity);
+    }
+
     /// <summary>
     ///     Adds an new component to the <see cref="Entity"/> and moves it to the new <see cref="Archetype"/>.
     /// </summary>