The Lich King
Wrath of the Lich King is actually a gauntlet event where you must escape from the Lich King himself. It serves as the third boss encounter in the Halls of Reflection. It is tied to the achievement 
We're Not Retreating; We're Advancing in a Different Direction..
NPC map not available, NPC may be spawned via a script
We're Not Retreating; We're Advancing in a Different Direction..