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    George Foreman

    It’s hard to think of George Foreman as a scary guy after you’ve seen him hawking grills on TV, but in his heyday Big George was one of the most terrifying men to ever walk the squared circle. Foreman’s reputation in the ring was built on his sheer physical power, and when he first rose to the top he decimated many of the sport’s best heavyweights.

    Foreman used to psych himself up for a fight by telling himself that he was literally going to murder his opponent, and when you watch him fight you can see lethality behind every blow. Just to prove you can’t take the fight out of the dog, Foreman also became the oldest heavyweight champion in history in 1994.