I liked the concept of switching between Heaven and Heck, but the game really needed to show that off a bit more. The art and sound were pretty good too.
Two weird things though. For starters the spacebar isn't captured, meaning you scroll down whenever you press space, which gets fairly annoying.
Secondly, it seems a bit strange that the duck isn't in the exact same position in both dimensions when you press spacebar. This could've been explained a lot better.
Overall, the game was still pretty good, it just needed a bit more polish and difficulty.