diff --git a/.todo b/.todo
index 22e7682..fd5944a 100644
--- a/.todo
+++ b/.todo
@@ -1,6 +1,5 @@
 FART To-Do List
 ===============
-- Fix subtractions of subtractions (inverting normals problem)
 - Shape definitions / reusability
 - Add distribution infrastructure
 - Add maximum recursion depth option / parameter
diff --git a/scenes/subtract-subtract.fart b/scenes/subtract-subtract.fart
index 9431b42..11fe6bc 100644
--- a/scenes/subtract-subtract.fart
+++ b/scenes/subtract-subtract.fart
@@ -3,7 +3,7 @@ scene
 {
     options
     {
-        multisample 2
+        multisample 3
     }
 
     camera
@@ -17,6 +17,15 @@ scene
         position <-1, -3, 4>
     }
 
+    plane
+    {
+        position <0, 0, 1>, 1
+        material
+        {
+            color <0, 1, 1>
+        }
+    }
+
     subtract
     {
         box