Vadrigar

Untold centuries ago the Vadrigar, the mysterious Arena Masters, constructed the Arena Eternal for their own infernal amusement. Virtually nothing is known of these beings except that they savor the carnage and clamor of battle. As such, they have stocked the arena with the greatest warriors of all time. And you have just joined their ranks.

As a gladiator in the Arena Eternal, you must not only survive, but also win each and every battle against ever more powerful opponents. Don't worry overly much about getting "fragged." The Vadrigar won't be cheated of their favorite sport by a little thing like death. Those who fall are instantly restored to life and immediately thrust back into the battle, perhaps a little wiser for their misfortunes.

When the dust, blood, and gibs settle, all warriors will have earned the right to battle again, providing further entertainment for the Vadrigar. But only the warrior who has fragged the most foes will be lauded as the winner. The victorious gladiator advances to a more challenging array of arenas, until, at last, he or she faces Xaero, Lord of the Final Arena.

Source
Quake Wiki http://quake.wikia.com/wiki/Vadrigar