From WoWWiki
The unholy place where Orcs come to make sacrifices to their gods, and the Necromancers of the land gather to invoke the will of their dark masters. This is the only place where Necrolytes can be recruited to assist you in purging the land of Human settlements. The need for a blood offering has only recently been replaced by one of gold, and no assistance will be sanctioned until it is made. The immense, sacrificial alters used in the Necrolytes’ rituals must be built of the mystic Blackroot, hence a lumber mill must be used to locate and specially prepare the wood.WC1manO 29
