The Amphitheater of Anguish is a location and questline similar to the Ring of Blood. It is situated northeast of The Argent Stand in Zul'Drak and involves six different encounters. Each one is begun by talking to the owner, situated on a platform above the arena. By taking the quest, the encounter begins, and in order for it to end you must leave the arena, win, or die. It is also given by Gurgthock who has migrated to Northrend for more chances at fortune.
It is possible to complete the quest without having to kill any monsters. All you need is a warlock and a paladin. Get the warlock to SoulStone the paladin, then have the paladin aggro the first monster and use Divine Sacrifice on the warlock, then resurrect using the SoulStone and aggro the monster again. The monster will disappear immediately, giving you credit for finishing the quest.