Veles

Slavic God of Underworld, ruler of waters and treasures. I must explain : in Slavic languages, word for treasures is "blago", which refers to live stock, not money or land. Actually, in my native language (croatian), live stock is still called that. Thus his bull head. He is also referred to as "Old Snake", or a dragon, who lives in the roots of the World Tree (which, btw is not Nordic concept, but Indo-European). A bit more explaining : Dragons and snakes are seen as water creatures in Slavic mythology. I will not go into details here, just this : Veles is an enemy of Perun, and their constant battle is what keeps the world in motion.
Watercolor. Enjoy, and if you have any question about Slavic mythology, please, don't hesitate. If I know the answer and I am a former ethnology student), I'll be happy to answer it.