During the Mage Clan Wars, the Umbaru were in conflict with the Vizjerei Clan. As decades of savage warfare took their toll on the Umbaru's culture and minds, the clans began to search for any means to prevail over their enemies. They thus captured a mage to do their bidding, using the mage to gain control of the khazra—former Umbaru that had been transformed into the Vizjerei. They thus gained control over the khazra, and drove the Vizjerei out of Teganze.
This came at a price however, and the Umbaru found themselves in servitude to Zagraal, in exchange for their cursed power. The khazra became furious marauders, driven to raid villages and caravans to sate their bloodlust and procure sacrificial victims for their demonic master. Zagraal's reign came to an end when the khazra's fellow Umbaru tribes sent Witch Doctors to end the khazra threat to the region. After cutting through swathes of khazra, the Witch Doctors finally confronted Zagraal, and in a now legendary battle, slew the demon. With Zagraal's death, the khazra were left without a source of demonic power to draw on. Never again would they be the threat they once were.