I recently came across a colorization that turns the original black and white/green version of Pokémon Red for the GameBoy into a proper GameBoy Color title. This sent me down a bit of a rabbit hole, but the sheer number of hacks that have been made over the course of several decades is slightly overwhelming, so I'd love to get a decent first selection by hearing which are your favorites that have improved or transformed console and handheld games in meaningful or entertaining ways.
Thanks in advance!
it's wild just how many Pokemon ROM hacks there are. there's one that recreates Sword and Shield on the GBA and it's pretty wild how faithful it is, it even has the raid battles. another cool one is Emerald ROWE which is an open world conversion where you can start anywhere. it uses some advanced hardware features so it doesn't work in every emulator
there's a hack of Sonic 3D Blast for the Saturn that basically chains all of the special stages into their own game, it's a very cool look at what a true 3D Saturn Sonic could have been, even if the stages are all just halfpipes
if you count translations, i have poured an ungodly number of hours into Shiren the Wanderer 2 on the N64 (different from the Shiren 2 on the DS). it's another one that doesn't always play nice with emulators but if you take copious savestates you'll be fine. each of the post-game dungeons is essentially a whole new game, and while i'm usually not much of a completionist i just can't put it down
I'm definitely counting translations! Being able to play games that would otherwise be behind a language barrier is a wonderful thing.