Randy Couture is one of the greatest ambassadors for the sport, and his longevity as a fighter is a testament to his abilities as an athlete. He was the first fighter to win title belts in two weight classes, and he holds the distinction of being the oldest title winner ever. Couture specialized in taking down his opponents and pounding them into submission. Its game over if he ever mounts you, as there's no escaping his merciless ground-and-pound game.