I'm gonna say Foreman...when renowned boxing figures think that a fighter may literally kill Ali or physically maim him, then you must have been a BAD man.
mike tyson's defense in his prime was out of this world. it's tyson for me. i'll never forget that walk to the ring against god knows who where it was just him walking and a guitar riff, it was the scariest thing for me as a kid.
Vitali Klitschko. He towers over you and has that if he dies he dies aura about him, and he will prolong the beating for a long time unlike the others mentioned who will put you to sleep quickly.
Roy Jones Jr, at his utter peak, was downright ridiculous to watch (think the type of heat he came out and blitzed Montell Griffin with in their rematch).
Tyson was crazy in his prime, but his peak wasn't anywhere near Roy's peak.
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