The angrier he gets, the stronger he gets—and Bruce Banner's gamma-irradiated alter ego has gotten angry enough to crack continents and punch through dimensions. The Hulk's strength has literally no known upper limit, he regenerates from virtually any wound, and his thunderclap can level city blocks. The only thing scarier than fighting the Hulk is the realization that he hasn't even started trying yet.

The ultimate team player of the animal kingdom, the gray wolf hunts in coordinated packs with military precision that would make Navy SEALs jealous. Individually, a wolf can sprint at 40 mph and deliver a 400 PSI bite—but its true weapon is pack tactics that can exhaust and overwhelm prey ten times its size. They don't fight fair, and that's exactly why they win.