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@@ -208,6 +208,8 @@ to:
 - ensure that the board's layout / draw methods are called by calling `board.setNeedsDisplay()`
 
 **Do not add any externally-accessed methods or properties in your custom view.**
+All communication from view controller to view should be from the
+`ButtonTiles` in the custom view's `subviews` array.
 
 ## Task 4: Animation
 Implement tile animation entirely in your `BoardView` class: