A drow prince. He is allegedly behind the attacks on Phaervorul, and the leader of the Orcus cult there.
More details learned from Matron Ulvrain: Zirithian was a drow noble from Phaervorul. He turned away from Lolth to worship Orcus and disappeared in exile. He returned with an army of undead and laid siege to the city.
More details learned from “The Keeper”: Zirithian struck a bargain with Orcus after he discovered the portal to Deadhold. In his bid for power, Orcus promised to raise him to exarch status if Zirithian could provide Orcus ample sacrifices. The raid on Phaervorul was the first step in this process. The next step involves the sacrifice of worthy champions.
Recent updates. Now deceased at the hands of the Adventurers.