Contest of Claws

Beastmasters can be found all over Naggaroth, for they are drawn to wherever potential pets can be found. However, there is a traditional rivalry between the rulers of Karond Kar and Clar Karond, who each claim to have dominion over the most accomplished Beastmasters of all. This claim is settled, once each year, in the Contest of Claws -- a formal battle between whichever Beastmasters from the two cities are prepared to put their lives, and those of their charges, at risk for the fleeting honour of their city. The Contest of Claws is always a closely fought affair, with both sides arranging 'accidents', assassinations and as many other forms of skulduggery as possible to ensure their rightful victory.1a

Source
Warhammer Armies: Dark Elves (8th Edition) -- pg. 49