Bai-Ulgan, also referred to as Bai-Ulgen, Ulgen, or Ulgan; a Siberian creator-deity, usually distinct from Tengri but sometimes identified with him in the same manner as Helios and Apollo.

Bai-Ulgan may be analagous to the demiurge of Gnostic theology. The birch tree, regarded as a cosmic axis between earth and sky, was regarded as sacred to him, as was the horse (horse-sacrifice was a part of his worship). He was regarded as the patron god of shamans and the source of their knowledge.

Resources

Horse Sacrifice and the Shaman's Ascent to the Sky