Son of Don and Beli Mawr, king of Brittany and brother of King Lludd of Britain. Not mentioned in History of the Kings of Britain, but mentioned in the Mabinogion. Hero of the tale "Cyfranc Lludd a Llefelys." As a god, he seems to be connected to speech and wisdom, like the Irish Ogma.
However, alternately his name is given as Lleuelys, which leads Patrick Ford, in his translation The Mabinogi and Other Medieval Welsh Tales to surmize that Lleuelys may be Lugh, as Lludd is certainly Nudd, who in Irish literature is Nuada, and that the tale of Lludd and Lleuelys is analoguous to the Irish story of Lugh aiding Nuada in the battle against the Fomorians.