Sovereign of Desolation

In your hands lies the still-beating heart of the Dreadlord Mephistroth, ruler of the Rock of Desolation. You and your expedition foiled his plans of using Karazhan as an entry point to invade Azeroth yet again. Expelled into the Great Dark Beyond forever, this is all that remains of the nefarious schemer.

You should bring it to someone able to expunge its life, just to be sure.

This horrible stench! <name>, what have you brought with you?!

What a horrid prospect. To think we stood at the precipice of another invasion by the Burning Legion. <name>, your actions and those of your compatriots did not only save Azeroth from another war, but also quelled the threat of one of the most powerful dreadlords known to us. Second to only Tichondrius, the harbinger of the Legion?s invasion seven years ago, legends of his might circulated the Council of Six in Dalaran. Unimaginable to see such a commanding figure finally meet its demise.

You were correct in bringing his vile heart to me. I am able to burn the fel essence from its flesh, albeit very taxing for my body. That is but a small sacrifice, however. Nothing is too little when given the opportunity to remove such a putrid presence from our world. Whatever remains of this, you can keep. As a trophy; a remembrance of the feat you accomplished this day.