There are multiple accounts of Ulgan's origins, with little, if any, evidence to back up any of them. One such account holds that the Ulgan Progenitor was once a mortal man in a Siberian village. Unknown to Ulgan, the ruling element in his being was spirit, and this made him a fitting candidate for certain dark rituals. The Ulgan demiurge, who some Ulgan call Tengri, sought Ulgan out, in the hope of making a spirit-riven slave from him. Tengri sent Ulgan into Twilight, where he was torn apart by the spirits, and then proceeded to rebuild Ulgan's body.
What Tengri did not anticipate, however, was that Ulgan would retain his awareness throughout the process. And he remembered who had done this to him. Ulgan turned on Tengri, killing him, and proceeded to do to him what Tengri had done to him, creating a new Promethean from Tengri's remains. This new Promethean, however, did not retain Tengri's memories or his soul, being instead an entirely new creation. Ulgan named this Promethean Erlik, and he was the first of Ulgan's creations.