Slay 10 Hounds of Culuthas and 5 Eyes of Culuthas. Then return to Nether-Stalker Nauthis at the Stormspire in the Netherstorm.
A few weeks ago, the Burning Legion moved into the Ruins of Farahlon, thwarting our plans to excavate the site for its artifacts.
Then earlier today, I learned that one of their dreadlords, Culuthas, somehow killed off all of the other Burning Legion. He has since summoned in demons that serve him.
[class], I want you to go up to those ruins to the northeast and rid them of their demon infestation.