The Groac'h of the Isle of Lok (French: La Groac’h de l’Île du Lok)[1] is a Breton fairy tale collected by Émile Souvestre in Le Foyer breton.
They lamented their poverty, dreaming of a little farm where they could live, until Houarn decided to go away to seek his fortune.
Bellah gave him a bell that could be heard at any distance, but only rang to warn of danger, and a knife that broke spells with its touch.
He walked until he heard of the Groac'h of the island of Lok, a rich fairy; no one had ever gone after her treasure and come back.
He prepared to jump off and swim, but it dived and carried him to the lake bottom, where the Groac'h had her palace.
She took her stick, and it turned into a horse, and then into a bird that carried her to a nest, where a little black man was.