Uther

Birth
Uther was born on Dragon Snout Cliff, the home of many monks. He trained in monk fighting styles, but thought of their pacifism as stupid and wanted to kill. When he tried to leave, the monks attempted to stop him, but he easily killed them all with two daggers he had received from his father.

Assassins
Uther traveled to England to become a professional underworld assassin, and came to the top very quickly with his daggers. He personally killed 20,000 targets during this time, always killing two at a time with his two daggers. He eventually met another assassin named Igraine, who he gifted one of his daggers and married. The two went on to assassinate 40,000 more targets before settling down in an unremarkable town. He had two kids with Igraine, named Arthur and Morgan, but Arthur ended up being "kidnapped" by Merlin.

Arthur's Reign
Years later, Arthur returned to his old town with the Round Table to destroy the assassin families. Uther fought against the knights and temporarily dueled with Arthur before being killed by him. His death served as inspiration for Morgan to destroy the Round Table as revenge.