Barbegazi are monsters which resemble dirty, hairy rocks. Unlike rocks though, they also have very sharp teeth and are capable of imitating human speech. They live in the deepest depths of mines and caves, often the same locations where one might also find vespertyls. They are mentioned in The Tower of the Swallow, the sixth book in the Witcher series and the fourth novel in the Witcher saga.
See the GWENT standalone game version card: Barbegazi