Notes:

In a recent video the countdown creator RabbidLuigi made, he excluded Yoshi's Island because it wasn't a "Mario" Game… and then not even two sentences later includes Donkey Kong Jr. because it's a "Mario" sequel with "Mario" in it.

Argue about Yoshi's Island and Wario Land all you want, they're still leagues more qualified than Donkey Kong Jr. because at least they have Mario in their title. DK Jr. doesn't even have Mario in the game, because that's not Mario as the villain, that's Jump-man.