He's a "God" from the Elderscrolls Games. He's in Skyrim and also in Morrowind, I don't know if he's in any of the other games. I've only met him in Morrowind jet. There he didn't really had a deer head, only a weird head with antlers. And he could turn into a wolf with antlers or a bear with antlers. He was also the one who turned people into werewolfs. This is what he looked like: [link] I'm not sure if he has a real dear head now but he was supposed to be a god of the wild animals and werewolfs were the wild animal version of normal humans.At least that's how I remember it.