Mubix is the planet that video game characters are from in the comics. Mostly humans and anthropomorphic animals live there. Note that while originally, some of the anime-like storylines also had hacked games set on Mubix, the manuals have always had Mario living on Planet Nintendo, and since post-Super Smash Bros. Brawl `games have followed the storylines in all regions, it's safe to say Mario has always lived on Planet Nintendo in the games. Though other old main game manuals never mentioned what world Mario lived on.