I have a device, the Demoniac Scryer, that can analyze fel magic.  I would have you use the Scryer, but first... you must appease it.  The Scryer, you see, has trapped within it a creature of vast intelligence and its needs are, shall we say, quite eccentric.$B$BTo appease the Scryer, you must kill orcs.  Specifically, they must be Shattered Hand orcs -- the Scryer demands their souls.$B$BReturn to me when the souls are reaped.  You will find the orcs north, and south, and surrounding... Hellfire Citadel.