Dreamseeker Trilogy Series by Jenny Oldfield

Four Winds and his spirit horse, Silver Cloud, now face the second task set down by Ghost Horse—to fetch a feather from the highest mountain. They travel north, crossing forests filled with bears, coyotes, and wolves. Along the way they come across their old adversary, Thadodaho, the evil thunder spirit with snake-hair, turtle claws, and the feet of a bear... moreFour Winds and his spirit horse, Silver Cloud, now face the second task set down by Ghost Horse—to fetch a feather from the highest mountain. They travel north, crossing forests filled with bears, coyotes, and wolves. Along the way they come across their old adversary, Thadodaho, the evil thunder spirit with snake-hair, turtle claws, and the feet of a bear. But to get to the summit of Mount Kivioq they must face their most powerful enemy so far, in the shape of Iron Eyes—a treacherous and cruel wolf spirit with an awesome helper. less