Count D'if was the leader of the Cybock Imperium, and was described by the Twelfth Doctor as “a deadly, cunning, ruthless tyrant”.
After defeating the Hyperions, Rassilon and the Alliance of Races embarked on another campaign against threats to universal harmony. One such enemy was Count D'if of the Cybock Imperium. After the war reached a stalemate, Rassilon challenged D'if to a game of Rassilon's roulette. If D'if won, the Alliance would leave the Cybock Imperium alone, and if D'if lost his entire history would be wiped from existence. D'if was a notorious gambler, and accepted the proposition. (COMIC: Gangland)