Peter Stumpp's Wolf Skin

Origin
Peter Stumpp was a German famer in the 16th century who was accused of being a serial killer and cannibal dubbed the “Werewolf of Bedburg”. Tortured by the rural community, he confessed to have practiced black magic as a boy and that the Devil had given him a magic belt that allowed him to switch from human to wolf form and back. For 25 years, he allegedly fed on local livestock and villagers until they executed him for his supposed crimes.

Effects
The user gains fur, increased agility, sense of smell and sight. But, the user slowly gains a hunger for meat; if used for too long, they can lose their human instincts and retain wolf instincts.