AM2R was one of the first incredibly impressive fan projects to come out of a Nintendo property. Because of that, it was one of the first to get absolutely shredded into oblivion by C&D orders. It's only because of that happening that I ever heard of it to begin with. AM2R builds tension better than some of the actual games. The planet is more lively than that of Samus Returns, and it helps them stand apart as two different but equal experiences. All Metroid 2 really needed was Zero Mission controls and this did that and so much more.