Lycanthropy

Lycanthropy is a condition where a person is capable of transforming into a non-human animal form, with its most common form being a werewolf.

Mainstream Smurfs Media
In mainstream Smurfs media, lycanthropy appears at least twice in the cartoon show. In "Wolf In Peewit's Clothing", Radna used wolf gravy to transform Peewit into a werewolf so that he could capture a few Smurfs to restore Radna's magical abilities. In "I Was A Brainy Weresmurf", Brainy became a weresmurf when he was scratched by a moon flower.