Art is great, audio is great and it's a ton of fun. I like how hard the later stages are. My only problems with this game are how
1) the jumping can be very hard to time. If you could hold jump to immediately juump upon landing, it would certainly improve things.
2) the disappearing parts seemed a bit unpredictable. I'm not sure how they are supposed to work, but they're probably not working as intended.
Nonetheless a lot of fun to play!