Son of the sorcerer Eliavres. Lorigal’s mother was a mare.
Eliavres had been forced to copulate with the mare after King Caradoc of Nantes found Eliavres sleeping with Caradoc’s wife. Rachel Bromwich (Grout, 43) suggested Lluagor (‘Host-Splitter’), Caradoc’s horse in the Triads, as an origin.
Source
First Continuation of Chrétien’s Perceval | Attributed to Wauchier of Denain, c. 1200