The Undead Lord

The Undead Lord is a sinister lord of evil, he commands a small army of Undead. His army is iconically called the Lich King's Army. Obviously a reference to WoW's Boss Character "Arthas, the Lich King."

The Undead Lord's Background
All that is known of the Undead Lord is that he was a Vampire who was loyal to Harkon. He became Harkon's successor's, Valgeir, Champion. He named himself "The Undead Lord" upon gaining the Armorset of the Undead and the sword "Valgeirian."

Note: The Armorset and the Sword is a reference the the Lich King's armor and weapon.

The Undead Lord's Wrath
Nothing is known of the event known as "The Undead Lord's Wrath."