Nukeball

Nukeball was a favourite sport among a number of Judoon, but it was outlawed on their home planet so the population was not wiped out.

Despite this, it was still played illegally, and often a star system would explode, which signified a Pyrrhic victory. (PROSE: The Coming of the Terraphiles)

Behind the scenes
Nukeball is depicted as a card to collect and play in the game Doctor Who: Worlds Apart.