Lü Bu

Lü Bu started as subordinate to the minor warlord Ding Yuan, murdered him, and defected to the powerful Dong Zhuo. In 192, he killed Dong Zhuo too after being instigated by Wang Yun and Shisun Rui, then got driven from Chang'an by the dead man's followers. For the next three years he bounced between patrons - Yuan Shu, Yuan Shao, Zhang Yang - briefly seizing Yan Province from Cao Cao in 194 before losing it back within two years. In 195 he turned on Liu Bei, who had given him refuge in Xu Province, and took the province for himself. He allied with Yuan Shu, broke with him when Yuan declared himself emperor, then sided with him again in 198 - which brought Cao Cao and Liu Bei down on him together. Captured at the Battle of Xiapi on 7 February 199, he was executed on Cao's order. His volatile temperament and relentless betrayals ended the career of the age's most formidable fighter.