Tyrannus is a terrible force who will no doubt demonstrate his powers to those brave enough to enter the Pit of Saron. The scourgelord must die if players hope to make their way into the third and final wing of this dungeon.
Scourgelord Tyrannus is a human death knight mounted upon his frostbrood wyrm, Rimefang, encountered in the Pit of Saron, the second wing of the Frozen Halls.
His death is the objective of the storyline quest Deliverance from the Pit (Alliance) / (Horde).

by The Path to the Citadel Quest | WoW Reviews & Guides, on December 12 2009 @ 7:39 pm
[...] Description They’ve put our captured soldiers to work in the quarry! Kill their captors and set them free, hero, and do it quickly. We will need their aid when we confront Scourgelord Tyrannus. [...]