Guessed by The_Liquid_Laser
Easily the best 2D platformer I've played. This is one of those where you can instantly recognize any level just from seeing a screenshot, because they are each so unique and so creative they really just stick with you - while still being coherent enough to maintain a certain level of immersion, which is far too often not the case with other platformers (I'm looking at you, Mario). There's not a single stage in this game that isn't loads of fun, or features amazing music, or introduces interesting ideas - and most of the time they're doing all of those. It's just... really, really fucking good. But yeah, the soundtrack goes a level above everything else, it's absolutely unreal.