Voltarus

Voltarus is a Scourge necropolis located in the northwest of Zul'Drak, which hovers above blighted pools of plague known as the Reliquary of Pain, near the border with the Storm Peaks.

During the war against the Lich King, after he betrayed his own people to the Lich King, Overlord Drakuru was given control over the necropolis Voltarus. From there, Drakuru had a plan to infuse captured troll chieftains with blight and transform them into misshapen weapons in his efforts to conquer all of Zul'Drak for the Scourge.

The second floor can only be visited during a few quests players receive from Drakuru. The transporter will stop working after the chain is completed.