In native American lore (my grandfather who is Algonquin Indian told me this) there is a creature that is called the Windigo. Its a shape shifter. It can be animal, human, mist and even possess. Its seen with large glowing eyes and dark human looking body sometimes with fangs. It walks upright unless in animal or mist form. It can change rapidly these forms. Sometimes smells so bad you wanna vomit. It can speak like that of man or creature or animal. Can possess humans as well to cause them to kill or torment them. Some say its from an evil person who hasn't crossed over, or one that was possessed by in in life then died, or a demon itself. In books I have read it states that throwing feces at it can scare it away or shamanic ways of protection or purification.