Kaizo Mario World 2, also known as Asshole Mario 2, is a hack created by T. Takemoto for his friend R. Kiba. It features extremely sadistic, unique and groundbreaking level design. This is also the hack that started it all, since the kaizo genre wasn't existent beforehand. The literal translation of "Kaizo Mario World" is "自作の改造マリオ（スーパーマリオワールド）を友人にプレイさせる", or in plain English, "Making my friend play through my Mario hack (Super Mario World)". Kaizo is a rough translation of the word "modify" or "change" in Japanese.
Guys, it's Kaizo Mario World. Who really cares about the floating munchers. I think this is more than notable enough to be an exception to the rule. Not to mention it wasn't even submitted by the creator.