Out of those guys it has to be Mike... Shavers is the only who comes close to him when it comes to one punch ko's. Foreman could pummel a guy, but he never cleanly ko'ed a good opponent like Mike or Shavers. The reason why I say Mike over Shavers is that he is about 20 pounds bigger, alot faster, and he just the same type of leverage into his punches, but like I said Foreman was immensely strong, but not ko type puncher, and I don't think he was any stronger than Mike who weighed as much as him, but was 5 inches shorter.