Spriggan
Spriggans are mythical creatures in the Cornish folklore , known as thieves, robbers, burglars and villains . They are also supposed to rob babies from their cradles and instead leave behind a hideous changeling . Furthermore, according to popular belief, they are able to conjure up a hurricane to destroy the grain harvest. Otherwise they do not shrink from any evil deed.
They are small and ugly, but they can puff up huge, which is why it was believed that they were ghosts of deceased giants.
Spriggans make themselves useful as guardians of treasure hidden in the hills.