I had the same problem until I realized my understanding of the word "mash" is not the same as the game developers! For example, one of Stan's special moves requires you to "mash" A and D until you see the flash. This does NOT mean hold down A and D together. You need to "TAP" back and forth between A and D to make him spin and then he will flash. Butter's has a similar move that asks you to "mash" 2 buttons and again, they should have said alternately tap A and D. Hope this helps!