Aside from Fabricio Werdum, Frank Mir may be the very best submission artist the heavyweight division has ever seen. Mir has nine submission wins to his name, and actually holds the record for most submission wins in the history of the UFC heavyweight division. He is also the only man in UFC history to win a bout by toe-hold submission (seriously). For me, Mir lands this high up on my list for not only his skills, which speak for themselves, but for the brutality of his submission skills. The former UFC heavyweight champ sunk in a nasty knee bar on Brock Lesnar, and actually broke the arm of Brazilian legend Antonio Rodrigo Nogueira via kimura. Mir is deadly on the mat, and although he has been struggling over the last few years, he is still one of the UFC’s best mat tacticians.