Playability:
Nice precision platformer with world swapping mechanics. A really good base for something that could become incredibly interesting. I did find that it's easy to get stuck in walls and floors by swapping worlds so there may need to be a test pass on this.
Theme:
Didn't really feel the theme come through on this one but that's alright. You've made something very compelling regardless.
Cleverness:
Really loved the instant swapping between worlds. Lots of room for puzzles in level design.
Artistic Style:
Beautiful pixel art and nice tunes to back them up. Good job.