Veles s a major Slavic supernatural force of earth, waters and the underworld, associated with dragons, cattle, magic, musicians, wealth and trickery. He is the opponent of the Supreme thunder-god Perun, and the battle between two of them constitutes one of the most important myths of Slavic mythology. No direct accounts survive, but reconstructions speculate that he may directly continue aspects of the Proto-Indo-European pantheon and that he may have been imagined as (at least partially) serpentine, with horns (of a bull, ram or some other domesticated herbivore), and a long beard. By all accounts, he was considered as an evil god with gray shades.
Ancient Slavs viewed their world as a huge tree, with the treetop and branches representing the heavenly abode of gods and the world of mortals, whilst the roots represented the underworld. And while Perun, seen as a hawk or eagle sitting on a tallest branch of tree, was believed to be ruler of heaven and living world, Veles, seen as a huge serpent coiling around the roots, was ruling the world of dead. This was actually quite a lovely place, described in folk tales as a green and wet world of grassy plains and eternal spring, where various fantastic creatures dwell and the spirits of deceased watch over Veles' herds of cattle. In more geographical terms, the world of Veles was located, the Slavs believed, "across the sea", and it was there the migrating birds would fly to every winter. In folk tales this land is called Virey or Iriy. Each year, the god of fertility and vegetation, Jarilo, who also dwelt there during winter, would return from across the sea and bring spring into the world of the living.
That enough about Veles, although there is still much about him. :D
Tomorrow I will represent you God Perun! Enjoy you reading! Slava! :D