Source: i09.com

4. Galactus

Ah, Galactus, the two-eyed, two-horned flying purple planet eater.

Galactus was born Galan, a citizen of the universe that preceded ours. But when that one ended with the big bang (just roll with it, actual scientists), he absorbed all that power and was reborn as Galactus the Devourer.

His job was to eat planets, usually with some sort of herald in tow. His heralds were hyper-powered individuals, and he would send them off to pick out planets he could feed on. And he picked earth a couple of times. The Fantastic Four were usually able to halt his efforts. At one time, they saved his life and made him promise to never, ever try to eat Earth again.

They thereby doomed billions, if not trillions, of lives. Good job, FF. Galactus has been changed and revitalized a couple of times. He recently had his polarity shifted and became the Lifebringer. He was orange.