Grumbling Bear takes a great deal more from bears than just the name.  He towers over other men and is broad of shoulder.  It is hard to tell where his rich brown hair ends and the fur covering his back, shoulders, and arms begins.  Instead of normal hands he has something in between a bear's paws and a man's hands and he has an elongated muzzle full of sharp teeth.  Very clearly a skinwalker, he lives constantly somewhere between being a man and being a bear.