diff --git a/asdlteroids.csproj b/asdlteroids.csproj
index 5524382..448db1d 100644
--- a/asdlteroids.csproj
+++ b/asdlteroids.csproj
@@ -5,6 +5,9 @@
     <TargetFramework>net6.0</TargetFramework>
     <RootNamespace>asdlteroids</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
+    <PublishTrimmed>true</PublishTrimmed>
+    <PublishReadyToRun>true</PublishReadyToRun>
+    <PublishSingleFile>true</PublishSingleFile>
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
diff --git a/src/Scene.cs b/src/Scene.cs
index 1498d7d..763eeaf 100644
--- a/src/Scene.cs
+++ b/src/Scene.cs
@@ -10,6 +10,7 @@ class Scene
     private Renderer renderer;
     private static Scene? instance;
 
+    public Ufo ufo;
     public HashSet<Shot> Shots;
     public HashSet<Asteroid> Asteroids;
     public int Score = 0;
@@ -20,6 +21,7 @@ class Scene
     public Scene(Renderer renderer)
     {
         this.ship = new Ship(SCREEN_WIDTH / 2, SCREEN_HEIGHT / 2);
+        this.ufo = new Ufo(SCREEN_WIDTH / 2, SCREEN_HEIGHT / 2);
         this.ui = new UI();
         this.Shots = new HashSet<Shot>();
         this.Asteroids = new HashSet<Asteroid>();
@@ -54,6 +56,7 @@ class Scene
             var entities = new List<Object>();
             entities.Add(ship);
             entities.Add(ui);
+            // entities.Add(ufo);
             entities.AddRange(Shots);
             entities.AddRange(Asteroids);
 
diff --git a/src/engine/KeyState.cs b/src/engine/KeyState.cs
index 5793a70..71ffa07 100644
--- a/src/engine/KeyState.cs
+++ b/src/engine/KeyState.cs
@@ -9,7 +9,7 @@ class KeyState
     {
         var origArray = SDL_GetKeyboardState(out var arraySize);
         this.keys = new byte[arraySize];
-        Marshal.Copy(origArray, keys, 0, arraySize);
+        Marshal.Copy(origArray, this.keys, 0, arraySize);
     }
 
     public bool isPressed(SDL_Keycode keycode)
diff --git a/src/entities/UI.cs b/src/entities/UI.cs
index 3c3b08d..17a6b84 100644
--- a/src/entities/UI.cs
+++ b/src/entities/UI.cs
@@ -59,5 +59,7 @@ class UI : Renderable
         }
 
         SDL_RenderCopy(renderer.GetRaw(), texture, IntPtr.Zero, ref rect);
+        SDL_DestroyTexture(texture);
+        SDL_FreeSurface(surfaceMessage);
     }
 }
diff --git a/src/entities/Ufo.cs b/src/entities/Ufo.cs
new file mode 100644
index 0000000..071817b
--- /dev/null
+++ b/src/entities/Ufo.cs
@@ -0,0 +1,42 @@
+class Ufo : Logic, Renderable
+{
+    public int X, Y;
+
+    public Ufo(int x, int y)
+    {
+        X = x;
+        Y = y;
+    }
+
+    public void Render(Renderer renderer, double dx)
+    {
+        renderer.setColor(255, 255, 255);
+        renderer.DrawLines(new double[][]{
+            new double[]{X-Scene.SCALE*15, Y},
+            new double[]{X+Scene.SCALE*15, Y},
+            });
+        renderer.DrawLines(new double[][]{
+            new double[]{X-Scene.SCALE*15, Y},
+            new double[]{X-Scene.SCALE*6, Y+Scene.SCALE*6},
+            new double[]{X+Scene.SCALE*6, Y+Scene.SCALE*6},
+            new double[]{X+Scene.SCALE*15, Y},
+            });
+        renderer.DrawLines(new double[][]{
+            new double[]{X-Scene.SCALE*15, Y},
+            new double[]{X-Scene.SCALE*6, Y-Scene.SCALE*6},
+            new double[]{X+Scene.SCALE*6, Y-Scene.SCALE*6},
+            new double[]{X+Scene.SCALE*15, Y},
+            });
+        renderer.DrawLines(new double[][]{
+            new double[]{X-Scene.SCALE*6, Y-Scene.SCALE*6},
+            new double[]{X-Scene.SCALE*4, Y-Scene.SCALE*12},
+            new double[]{X+Scene.SCALE*4, Y-Scene.SCALE*12},
+            new double[]{X+Scene.SCALE*6, Y-Scene.SCALE*6},
+            });
+    }
+
+    public void Update(KeyState keyState, double dx)
+    {
+        //
+    }
+}