A prophecy was made in the Greenskin Tribes of the Great Desert that a mighty conqueror would be born during a double solar eclipse, blessed by the The Many Faces of God.
For some time it was believed that this mighty conqueror or "Shadowborn" was Zibrust. Before it was revealed in the events of A Gathering Storm, only Moirin Mhic Macdha realised the true identity of the Shadowborn was Wretch "Shadowborn", who was marked by Dezrael by being albino and hunchbacked. Upon Zibrust's death, Wretch's latent sorcerous abilities are unleashed, and he becomes a Mortal Avatar of Dezrael.