The idea takes some time/levels to really pay off, but it's interesting and offers a lot of possibilities. Nice surprises level after level (oh cool I can actually play after dying ! oh I can move the whole geometry instead of me ! etc...).
The art works well with the game, audio is pretty basic but does the job I guess.
It took a little bit of time (impressed by the time you had to do all these levels on top of the core of the game), but I completed all the levels in the end. Good job !