Upon the first appearance on stage of the ghoulish Betrayer, too, the Pentarch sailors gasped in fear and awe. For they recognized in him dark and terrible beings from their own tribal histories, the wars against which originally drove the Five Tribes and their kings into mutual aid and later strong alliance. In the Pentarch common tongue, they were known as Deviants — a root in common with the deviations unleashed by Wormwood, and his supplicant servant Morbat, neither of whom Kremellian legends recollected.

Source: Pressed into Service – Quatrian Folkways – Medium