Game of Rassilon
From Tardis Wiki, the free Doctor Who reference
The Game of Rassilon was a practice within ancient Gallifreyan history in which members of lesser species were Time Scooped into the Death Zone on Gallifrey to fight for the amusement of the Time Lords. (TV: The Five Doctors) After it was clear they "[played]" the game too well", the Daleks and Cybermen were excluded from the blood sport. (PROSE: Dalek Combat Training Manual) Eventually, Gallifrey moved past its ancient ways, yet President of the High Council Borusa later revived the game in a plot to achieve immortality. (TV: The Five Doctors)