This was great! I actually kind of wish there was more. This is insanely well polished in just three days, the platforming felt goof and the art looked great.
I will say though, I don't know if this is intended but you can definitely get infinite vertical height by quickly pressing jump, z, then x in that order repeatedly. It makes creating puzzles for this game quite difficult since the player can move vertically any amount with no need for platforms.