What a pleasing game!
Enjoyment: It's a really fun, yet simple mechanic.
Concept: The idea of a level that gets harder and harder is cool.
Presentation: Art style is striking, music is nice (and the option to mute it is a nice touch). My only complaint is that there were no instructions. I poked at my keyboard for a bit looking for a jump button.
Use of Limitation: I think it would be cool if the changes to the level were based on your actions. For example, a spike spawns where you landed before. Since the changes are preset, is it really a single level?
Overall, I really liked this entry.