diff --git a/Assets/Desert/Runtime/Dispenser/Dispenser.cs b/Assets/Desert/Runtime/Dispenser/Dispenser.cs
index d3ff1db..c1d4966 100644
--- a/Assets/Desert/Runtime/Dispenser/Dispenser.cs
+++ b/Assets/Desert/Runtime/Dispenser/Dispenser.cs
@@ -28,12 +28,12 @@ namespace EscapeRoomEngine.Desert.Runtime.Dispenser
                 {
                     CloseHatch();
                     dispenseButton.Disable();
-                    _light.color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor.hdr;
+                    _light.color = Engine.Runtime.Engine.Theme.solvedColor.hdr;
                 }
                 else
                 {
                     dispenseButton.Enable();
-                    _light.color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor.hdr;
+                    _light.color = Engine.Runtime.Engine.Theme.puzzleColor.hdr;
                 }
             }
         }
diff --git a/Assets/Desert/Runtime/HoloButton.cs b/Assets/Desert/Runtime/HoloButton.cs
index 48f5283..f848355 100644
--- a/Assets/Desert/Runtime/HoloButton.cs
+++ b/Assets/Desert/Runtime/HoloButton.cs
@@ -23,13 +23,13 @@ namespace EscapeRoomEngine.Desert.Runtime
 
             ButtonEvent += (_, _) =>
             {
-                var color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor;
+                var color = Engine.Runtime.Engine.Theme.puzzleColor;
                 if (!Active)
                 {
-                    color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor;
+                    color = Engine.Runtime.Engine.Theme.solvedColor;
                 } else if (Pressed)
                 {
-                    color = Engine.Runtime.Engine.DefaultEngine.theme.activeColor;
+                    color = Engine.Runtime.Engine.Theme.activeColor;
                 }
                 
                 _material.SetColor(FresnelColor, color.hdr);
diff --git a/Assets/Desert/Runtime/Hoop.cs b/Assets/Desert/Runtime/Hoop.cs
index 9ee024d..cb147bf 100644
--- a/Assets/Desert/Runtime/Hoop.cs
+++ b/Assets/Desert/Runtime/Hoop.cs
@@ -28,12 +28,12 @@ namespace EscapeRoomEngine.Desert.Runtime
                 switch (type)
                 {
                     case PuzzleEventType.Restarted:
-                        var color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor;
+                        var color = Engine.Runtime.Engine.Theme.puzzleColor;
                         rings.ForEach(ring => ring.color = color.hdr);
                         _dispenser.Reset();
                         break;
                     case PuzzleEventType.Solved:
-                        color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor;
+                        color = Engine.Runtime.Engine.Theme.solvedColor;
                         rings.ForEach(ring => ring.color = color.hdr);
                         _dispenser.Solve();
                         break;
diff --git a/Assets/Desert/Runtime/Portal/DesertPortal.cs b/Assets/Desert/Runtime/Portal/DesertPortal.cs
index a60d48f..33e20a8 100644
--- a/Assets/Desert/Runtime/Portal/DesertPortal.cs
+++ b/Assets/Desert/Runtime/Portal/DesertPortal.cs
@@ -20,10 +20,10 @@ namespace EscapeRoomEngine.Desert.Runtime.Portal
                 switch (type)
                 {
                     case DoorEventType.Unlocked:
-                        _emission.color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor.hdr;
+                        _emission.color = Engine.Runtime.Engine.Theme.solvedColor.hdr;
                         break;
                     case DoorEventType.Locked:
-                        _emission.color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor.hdr;
+                        _emission.color = Engine.Runtime.Engine.Theme.puzzleColor.hdr;
                         break;
                 }
             };
diff --git a/Assets/Desert/Runtime/Puzzle A/Ball.cs b/Assets/Desert/Runtime/Puzzle A/Ball.cs
index b2e2305..90415df 100644
--- a/Assets/Desert/Runtime/Puzzle A/Ball.cs	
+++ b/Assets/Desert/Runtime/Puzzle A/Ball.cs	
@@ -18,8 +18,8 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_A
             set
             {
                 statusLight.color = value ?
-                    Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor.hdr
-                    : Engine.Runtime.Engine.DefaultEngine.theme.solvedColor.hdr;
+                    Engine.Runtime.Engine.Theme.puzzleColor.hdr
+                    : Engine.Runtime.Engine.Theme.solvedColor.hdr;
                 ring.rotating = value;
                 if (!value)
                 {
diff --git a/Assets/Desert/Runtime/Puzzle A/Terminal.cs b/Assets/Desert/Runtime/Puzzle A/Terminal.cs
index 4590e7e..ee56c22 100644
--- a/Assets/Desert/Runtime/Puzzle A/Terminal.cs	
+++ b/Assets/Desert/Runtime/Puzzle A/Terminal.cs	
@@ -46,12 +46,12 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_A
                 {
                     case PuzzleEventType.Restarted:
                         _ball.Active = true;
-                        terminalLight.color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor.hdr;
+                        terminalLight.color = Engine.Runtime.Engine.Theme.puzzleColor.hdr;
                         symbols.ForEach(symbol => symbol.Enable());
                         break;
                     case PuzzleEventType.Solved:
                         _ball.Active = false;
-                        terminalLight.color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor.hdr;
+                        terminalLight.color = Engine.Runtime.Engine.Theme.solvedColor.hdr;
                         symbols.ForEach(symbol => symbol.Disable());
                         break;
                     case PuzzleEventType.WrongInput:
diff --git a/Assets/Desert/Runtime/Puzzle B/PuzzleB.cs b/Assets/Desert/Runtime/Puzzle B/PuzzleB.cs
index dc99173..4b65a47 100644
--- a/Assets/Desert/Runtime/Puzzle B/PuzzleB.cs	
+++ b/Assets/Desert/Runtime/Puzzle B/PuzzleB.cs	
@@ -42,14 +42,14 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_B
                 switch (type)
                 {
                     case PuzzleEventType.Restarted:
-                        var color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor;
+                        var color = Engine.Runtime.Engine.Theme.puzzleColor;
                         crystal.Color = color;
                         lights.ForEach(emission => emission.color = color.hdr);
                         rotators.ForEach(rotator => rotator.Emission.color = color.hdr);
                         buttonActions.ForEach(action => action.button.Enable());
                         break;
                     case PuzzleEventType.Solved:
-                        color = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor;
+                        color = Engine.Runtime.Engine.Theme.solvedColor;
                         crystal.Color = color;
                         lights.ForEach(emission => emission.color = color.hdr);
                         rotators.ForEach(rotator => rotator.Emission.color = color.hdr);
diff --git a/Assets/Desert/Runtime/Puzzle C/Hole.cs b/Assets/Desert/Runtime/Puzzle C/Hole.cs
index 55a15f6..c01dda6 100644
--- a/Assets/Desert/Runtime/Puzzle C/Hole.cs	
+++ b/Assets/Desert/Runtime/Puzzle C/Hole.cs	
@@ -30,7 +30,7 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_C
             {
                 if (Active)
                 {
-                    var color = Engine.Runtime.Engine.DefaultEngine.theme.activeColor;
+                    var color = Engine.Runtime.Engine.Theme.activeColor;
                     
                     orb.Color = color.hdr;
                     Emission.color = color.hdr;
@@ -44,7 +44,7 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_C
             var orb = other.GetComponent<DispenserOrb>();
             if (orb != null)
             {
-                var color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor;
+                var color = Engine.Runtime.Engine.Theme.puzzleColor;
                 
                 if (Active)
                 {
diff --git a/Assets/Desert/Runtime/Puzzle C/Holes.cs b/Assets/Desert/Runtime/Puzzle C/Holes.cs
index 2ac51db..f17fece 100644
--- a/Assets/Desert/Runtime/Puzzle C/Holes.cs	
+++ b/Assets/Desert/Runtime/Puzzle C/Holes.cs	
@@ -31,7 +31,7 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_C
                 switch (type)
                 {
                     case PuzzleEventType.Restarted:
-                        var color = Engine.Runtime.Engine.DefaultEngine.theme.puzzleColor;
+                        var color = Engine.Runtime.Engine.Theme.puzzleColor;
                         _holes.ForEach(hole =>
                         {
                             hole.Enable();
@@ -41,8 +41,8 @@ namespace EscapeRoomEngine.Desert.Runtime.Puzzle_C
                         _dispenser.Reset();
                         break;
                     case PuzzleEventType.Solved:
-                        var solvedColor = Engine.Runtime.Engine.DefaultEngine.theme.solvedColor;
-                        var activeColor = Engine.Runtime.Engine.DefaultEngine.theme.activeColor;
+                        var solvedColor = Engine.Runtime.Engine.Theme.solvedColor;
+                        var activeColor = Engine.Runtime.Engine.Theme.activeColor;
                         _holes.ForEach(hole =>
                         {
                             hole.Disable();
diff --git a/Assets/Engine/Runtime/Editor/EngineEditor.cs b/Assets/Engine/Runtime/Editor/EngineEditor.cs
index 06914e5..17db950 100644
--- a/Assets/Engine/Runtime/Editor/EngineEditor.cs
+++ b/Assets/Engine/Runtime/Editor/EngineEditor.cs
@@ -43,7 +43,7 @@ namespace EscapeRoomEngine.Engine.Runtime.Editor
         {
             if (EditorApplication.isPlaying)
             {
-                Engine.DefaultEngine.CurrentRoom.Match(some: room => room.EnterRoom());
+                Engine.Instance.CurrentRoom.Match(some: room => room.EnterRoom());
                 UpdateUI();
             }
         }
@@ -52,7 +52,7 @@ namespace EscapeRoomEngine.Engine.Runtime.Editor
         {
             if (EditorApplication.isPlaying)
             {
-                Engine.DefaultEngine.CurrentRoom.Match(some: room => room.SkipRoom());
+                Engine.Instance.CurrentRoom.Match(some: room => room.SkipRoom());
                 UpdateUI();
             }
         }
@@ -61,8 +61,8 @@ namespace EscapeRoomEngine.Engine.Runtime.Editor
         {
             if (EditorApplication.isPlaying)
             {
-                Engine.DefaultEngine.CurrentRoom.Match(some: room => room.SkipRoom());
-                Engine.DefaultEngine.CurrentRoom.Match(some: room => room.EnterRoom());
+                Engine.Instance.CurrentRoom.Match(some: room => room.SkipRoom());
+                Engine.Instance.CurrentRoom.Match(some: room => room.EnterRoom());
                 UpdateUI();
             }
         }
@@ -73,7 +73,7 @@ namespace EscapeRoomEngine.Engine.Runtime.Editor
             {
                 if (!_registeredUpdateEvent)
                 {
-                    Engine.DefaultEngine.UpdateUIEvent += UpdateUI;
+                    Engine.Instance.UpdateUIEvent += UpdateUI;
                     _registeredUpdateEvent = true;
                 }
             }
@@ -82,9 +82,9 @@ namespace EscapeRoomEngine.Engine.Runtime.Editor
                 _registeredUpdateEvent = false;
             }
             
-            _passToNextRoomButton.SetEnabled(EditorApplication.isPlaying && Engine.DefaultEngine.NumberOfRooms > 1);
-            _skipCurrentRoomButton.SetEnabled(EditorApplication.isPlaying && Engine.DefaultEngine.NumberOfRooms > 0);
-            _skipAndPassButton.SetEnabled(EditorApplication.isPlaying && Engine.DefaultEngine.NumberOfRooms > 0);
+            _passToNextRoomButton.SetEnabled(EditorApplication.isPlaying && Engine.Instance.NumberOfRooms > 1);
+            _skipCurrentRoomButton.SetEnabled(EditorApplication.isPlaying && Engine.Instance.NumberOfRooms > 0);
+            _skipAndPassButton.SetEnabled(EditorApplication.isPlaying && Engine.Instance.NumberOfRooms > 0);
         }
     }
     #endif
diff --git a/Assets/Engine/Runtime/Engine.cs b/Assets/Engine/Runtime/Engine.cs
index 04a7b9d..bcce55d 100644
--- a/Assets/Engine/Runtime/Engine.cs
+++ b/Assets/Engine/Runtime/Engine.cs
@@ -12,7 +12,8 @@ namespace EscapeRoomEngine.Engine.Runtime
 {
     public class Engine : MonoBehaviour
     {
-        public static Engine DefaultEngine
+        public static EngineTheme Theme => Instance.theme;
+        public static Engine Instance
         {
             get
             {
diff --git a/Assets/Engine/Runtime/Measurements/Puzzle.cs b/Assets/Engine/Runtime/Measurements/Puzzle.cs
index b8d2531..ddfc006 100644
--- a/Assets/Engine/Runtime/Measurements/Puzzle.cs
+++ b/Assets/Engine/Runtime/Measurements/Puzzle.cs
@@ -27,7 +27,7 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
 
         public override string ToString()
         {
-            return $"{Engine.DefaultEngine.theme.GetPuzzle(ID)}: avg. {AverageTimeToSolve.ToTimeSpan():m':'ss} ({string.Join(", ", Measurements)})";
+            return $"{Engine.Theme.GetPuzzle(ID)}: avg. {AverageTimeToSolve.ToTimeSpan():m':'ss} ({string.Join(", ", Measurements)})";
         }
     }
 }
\ No newline at end of file
diff --git a/Assets/Engine/Runtime/Passage.cs b/Assets/Engine/Runtime/Passage.cs
index 01bfd70..fe47fce 100644
--- a/Assets/Engine/Runtime/Passage.cs
+++ b/Assets/Engine/Runtime/Passage.cs
@@ -12,7 +12,7 @@ namespace EscapeRoomEngine.Engine.Runtime
 
         internal Passage(DoorModule from)
         {
-            if (!from.IsExit && !from.description.Equals(Engine.DefaultEngine.theme.spawnDoor))
+            if (!from.IsExit && !from.description.Equals(Engine.Theme.spawnDoor))
             {
                 throw new WrongTypeException(DoorType.Exit, DoorType.Entrance);
             }
diff --git a/Assets/Engine/Runtime/Room.cs b/Assets/Engine/Runtime/Room.cs
index 3f22034..a41b5ef 100644
--- a/Assets/Engine/Runtime/Room.cs
+++ b/Assets/Engine/Runtime/Room.cs
@@ -83,12 +83,12 @@ namespace EscapeRoomEngine.Engine.Runtime
                 {
                     // generate a new room as soon as the player completes all puzzles in this one
                     case DoorEventType.Unlocked when !LastRoom && door.Equals(exit.fromOut):
-                        Engine.DefaultEngine.GenerateRoom();
+                        Engine.Instance.GenerateRoom();
                         break;
                     // start measurements on every puzzle as soon as the player enters the last room
-                    case DoorEventType.ExitedFrom when door.Equals(entrance.toIn) && Engine.DefaultEngine.CurrentRoom.Contains(this):
+                    case DoorEventType.ExitedFrom when door.Equals(entrance.toIn) && Engine.Instance.CurrentRoom.Contains(this):
                         _puzzles.ForEach(puzzle => Measure.StartMeasuring((PuzzleModuleDescription)puzzle.description));
-                        Engine.DefaultEngine.HidePreviousRoom();
+                        Engine.Instance.HidePreviousRoom();
                         break;
                 }
             };
diff --git a/Assets/Engine/Runtime/Space.cs b/Assets/Engine/Runtime/Space.cs
index a187d5c..76698d5 100644
--- a/Assets/Engine/Runtime/Space.cs
+++ b/Assets/Engine/Runtime/Space.cs
@@ -46,8 +46,8 @@ namespace EscapeRoomEngine.Engine.Runtime
             this.room = room;
             rrPlacement = GenerateSpaceDimensions(
                 entrance,
-                Engine.DefaultEngine.theme.minRoomSize.ProjectAtFloor(),
-                Engine.DefaultEngine.theme.playSpace.ProjectAtFloor());
+                Engine.Theme.minRoomSize.ProjectAtFloor(),
+                Engine.Theme.playSpace.ProjectAtFloor());
             
             // connect the space to its passage
             entrance.PlaceEntrance(new DoorModule(this,
@@ -119,7 +119,7 @@ namespace EscapeRoomEngine.Engine.Runtime
                     else
                         location = left ? TileLocation.W : right ? TileLocation.E : TileLocation.C;
                     
-                    var tileObject = Object.Instantiate(Engine.DefaultEngine.theme.spaceTile, _spaceTiles.transform, false);
+                    var tileObject = Object.Instantiate(Engine.Theme.spaceTile, _spaceTiles.transform, false);
                     tileObject.transform.localPosition = new Vector3(x, 0, z);
                     tileObject.showTile = location;
                 }
diff --git a/Assets/Engine/Runtime/UI/GameControl.cs b/Assets/Engine/Runtime/UI/GameControl.cs
index 8d8e0e9..ea0ae25 100644
--- a/Assets/Engine/Runtime/UI/GameControl.cs
+++ b/Assets/Engine/Runtime/UI/GameControl.cs
@@ -41,7 +41,7 @@ namespace EscapeRoomEngine.Engine.Runtime.UI
 
         private void Awake()
         {
-            _targetTime = Engine.DefaultEngine.initialTargetTime;
+            _targetTime = Engine.Instance.initialTargetTime;
         }
 
         private void Start()
@@ -82,7 +82,7 @@ namespace EscapeRoomEngine.Engine.Runtime.UI
             _timeElapsed = 0;
             
             // generate the first room if it hasn't been generated yet
-            Engine.DefaultEngine.CurrentRoom.Match(none: () => Engine.DefaultEngine.GenerateRoom());
+            Engine.Instance.CurrentRoom.Match(none: () => Engine.Instance.GenerateRoom());
             
             // start a new session
             Measure.StartSession();