Spriggans were depicted as grotesquely ugly, and were said to be found at old ruins and barrows ''guarding buried treasure'' and generally acting as bodyguards. Though usually small, they had the ability to swell to enormous size (they were sometimes speculated to be the ghosts of the old giants).
Certainly their disposition was poor, and they caused mischief to those who offended them. They sent storms to blight crops, and sometimes stole away mortal children, leaving their ugly changelings in their place. In one story, an old woman got the better of a band of Spriggans by turning her clothing inside-out (turning clothing supposedly being as effective as holy water or iron in repelling fairies) to gain their loot.