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!