Alak-Hul, the Darkblade

Alak-Hul, the Darkblade is a Hive Knight, foster son of Oryx, and the boss of The Sunless Cell. Alak-Hul and his consort, Verok, were present at the Hellmouth when Eris Morn and Eriana-3 led their fireteam to assassinate Crota, Son of Oryx. It was Alak-Hul and Verok's spawn that killed the Titan Vell Tarlowe. Following the raid, Alak-Hul and Verok instigated a rebellion against Oryx, but the rebellion was put down. Alak-Hul was captured by Oryx's warriors, and the Taken King decreed that Alak-Hul be imprisoned aboard the Dreadnaught, never to see the light again. But after Oryx retreated from the material realm, Eris wanted to make sure Alak-Hul couldn't assume the throne, and ordered for his elimination.