Grizzly BearvsWolverine

Wolverines (the animal, not the X-Man) have an absolutely legendary reputation for ferocity. They've been documented driving bears and wolves away from kills, fighting animals many times their size, and displaying a fearlessness that borders on psychotic. But reputation and actual combat outcomes are different things.

A wolverine weighs about 40-55 pounds. A grizzly weighs 400-900 pounds. That's a 10-20x weight difference. While wolverines have been known to harass bears and occasionally drive them off kills (usually through sheer psychotic aggression that makes the bear decide the meal isn't worth the hassle), actually killing a grizzly is another matter entirely.

The wolverine's advantages are real: it has incredibly thick skin, a stocky, muscular build, sharp claws, a powerful bite for its size, and a legendary pain tolerance. But a single swipe from a grizzly paw delivers enough force to shatter the wolverine's skeleton.