Super Mario World hacks are what Mario Maker should've been. They've progressed to the point where it's not just trolls trying to make impossible shit, but actual good levels and interesting ideas, which are more common than not.

Having said that, I really hope SMWCP2 at least has shorter levels than the first one. That hack had way too many levels that just went on and on for several sections at a time without checkpoints, to the point where I ended up putting down save states halfway through out of frustration.