#7. Frank Mir
In June of 2004, UFC Heavyweight submission specialist Frank Mir won his first UFC Heavyweight Championship, snapping the arm of former champion Tim Sylvia in half in just 50 seconds in front of a shocked and awed Las Vegas crowd.
Mir was a fighter with a one-loss record at the time and with his seemingly unrivaled submission abilities, was one who might have a long reign at the top of the mountain.
Unfortunately for Mir it was a battle with a motorcycle that ended his championship reign, not another mixed-martial-artist, as he was eventually forced to relinquish the title on August 12, 2005 due to his inability to defend it after snapping his leg in a motorcycle accident.
Mir would defeat former WWE Superstar Brock Lesnar in Lesnar’s UFC debut before recapturing a version of the title in his next fight, a second-round TKO of MMA legend Antonio Rodrigo Nogueira at UFC 92 in 2008.
Mir would never recapture the undisputed title, however, as he lost to Lesnar in their rematch at UFC 100, to this date the most successful UFC pay-per-view event in history, as 1.6 million people purchased the show to watch Mir and Lesnar battle for the second time.
After dropping the title, Mir would remain relevant for a while, sticking around the UFC top ten for several years before going on a four fight skid from May of 2012 to February of 2014, a losing streak that continues to this day. There is no denying, however, that in his prime Mir was one of the most dominant forces in the history of the heavyweight division.