The Mad Titan of Marvel's cosmic hierarchy, Thanos is obsessed with universal balance and willing to snap half of existence out of reality to achieve it. Even without the Infinity Gauntlet, he can trade blows with the Hulk and outthink Reed Richards. With it, he is essentially God—capital G—with a chin that could cut diamonds.

Born James Howlett but known to the world as Logan, Wolverine is the Canadian mutant who simply refuses to stay dead. His adamantium-laced skeleton is virtually indestructible, his healing factor can regenerate from a single cell, and his razor-sharp claws slice through anything short of Captain America's shield. Three centuries of combat experience make him the best there is at what he does—and what he does isn't very nice.