Valoku and his companion Zzeraku were two nether dragons whom spent most of their time hunting for prey in the vicinity of Hellfire Penninsula prior to the reopening of the Dark Portal. They were well known to a tribe of Broken whom were often the targets of their hunt.
Shortly after the surviving demons of the Third War under Lord Kazzak managed to reopen the Dark Portal and reunite with their kin on Outland, prompting the investigation of Tyrygosa, a blue dragon, one of the caretakers and investigators of magic. Zzeraku and Valoku came across Tyrygosa after she had been struck down by the Death knight Ragnok Bloodreaver. Tyrygosa recruited the help of the two nether dragons in locating her missing companion Jorad Mace but was mislead and attacked by Zzeraku before he flew off abandoning her. Valoku flew off behind him.
After Tyri and Jorad were reunited they gave chase but were once again confronted by Ragnok and his band of minions. Tyrygosa had once again lost her paladin companion and was disoriented when Valoku came to her rescue, taking her to the nether dragon lair.