A nifty hack made Mario a playable character in 1994's Donkey Kong Country

Mario and Donkey Kong have been rivals, frenemies, go-kart competitors and tennis partners. The Italian plumber once kidnapped Donkey Kong's son. DK once, uh, took over Mario's toy company (?) and stole a bunch of little figurines for some reason. They have history. What they haven't done, however, is appear as playable characters in one another's platforming adventures. Thanks to a nifty bit of hacking, that just changed. Mario is a playable character in a hacked version of the SNES classic Don...