Lord of the Desert, Lord of the Wate Land
Goon Sert, Goondesert, Goot Delsert
Brother of the Fisher King and uncle of Perceval in the Third Continuation of Chrétien de Troyes’s Perceval. One of Goon Desert’s daughters was a Grail Maiden. Called the Lord of the Desert (the Waste Land), Goon Desert ruled the castle of Quingragan, which was besieged by Espinogrés and his nephew Partinal. Partinal killed Goon Desert with the Grail Sword, which broke.
Perceval, during his visit to the Grail Castle, saw Goon Desert’s body on a bier. After learning the story, Perceval avenged Goon Desert’s death by killing Partinal. A similar episode is recounted in the Welsh Peredur, where the head of Peredur’s cousin is seen floating in a dish in the Grail Castle, though the murderers in this case are the Hags of Gloucester.
Source
Third Continuation of Chrétien’s Perceval | Manessier, c. 1230