Notes:

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Most people think that Waluigi’s first appearance was in Mario Tennis, but it’s a lesser-known fact that he was originally slated to be the star character in what would later be known as Super Mario RPG: Legend of the Seven Stars! It seems that the first version of the game didn’t do too well with test audiences, so they replaced Waluigi with Mario to give it more appeal.

Sadly, this box art is all the evidence we have of the game’s existence – it’s rumored that Shigeru Miyamoto keeps the only remaining copy locked in a basement, refusing to let it see the light of day ever again.