15Waluigi Was Created For Mario Tennis
Waluigi's first appearance was in Mario Tennis 64, released in 2000 for, obviously, the Nintendo 64. Interestingly enough, Waluigi was created more or less out of necessity. Mario already had a built in doubles partner in his brother Luigi, while arch nemesis Wario was left out in the cold when it came
to two on two. But necessity is the mother of invention, and thus, Waluigi was born and first introduced to the Mario universe. Imagine the inferiority complex this guy must deal with. His buddy Wario has been mixing it up with the Mario Brothers since 1992, but he can't pick up the phone and get Waluigi in on it until he needs someone to play tennis with? I know one yellow and purple jerk who's not getting a birthday party invitation this year.