Skin-changers were creatures who could take different forms at will. Little is known of their abilities; the only skin-changers identified by Tolkien were Beorn and his descendants (who could take the shape of a Man or of a bear), but evidently other skin-changers also existed.
It has been suggested that Radagast, a "master of shapes and hues",[source?] was able to change his form. This is especially indicated by his closeness to animals, and his almost disregard for the wars of Middle-earth.