Valanar

Prince Valanar is the Scourge overlord of the Borean Tundra. He rules from Naxxanar, a Scourge necropolis above the Temple City of En'kilah in the northern edge of the Tundra.

Valanar can also be found in Valiance Keep disguised as Counselor Talbot, manipulating the Alliance leadership in order to weaken it. This is not revealed until the quest Last Rites.

He is also shown in a vision for the quest Out of Body Experience, where he and three other San'layn resurrect Archmage Arugal from the dead.

=Death Knight (manga)=

All this time he was disguised as Counselor Talbot, ready to lead the Alliance forces in the hands of the Lich King. He was stopped by Thassarian.

=Icecrown Citadel=

Valanar, along with his brother Keleseth and Prince Taldaram from Ahn'kahet, has returned in Icecrown Citadel as members of the Blood Prince Council. The three princes were raised in undeath by the Lich King to avenge themselves upon their slayers and to act as bodyguards for Blood-Queen Lana'thel, the blood-queen of the San'layn. They were unsuccessful and defeated once again.

See WoWPedia