His depictions and characterisations variously portray a foolish and cowardly knight, a violently deranged madman, to the now-iconic image of King Arthur's beloved court jester.
Later, during the False Guinevere's reign in another work, Les Prophéties de Merlin, Dagonet, loyal to Arthur and still known as the fool, takes on the administration of the royal court.
There he is a feared and unpredictable madman whose backstory is revealed as formerly one of the best knights of Arthur who went insane when his newly-married love was abducted by his own friend, Helior of the Thorn, whom Dagonet then tracked down and killed.
In a markedly more positive (and best known today) characterization by Thomas Malory in his seminal Le Morte d'Arthur, Dagonet is King Arthur's court fool who has been knighted as an award for his loyalty and comedic talents.
In a rewrite of a scene from the Prose Tristan, Kay arranges for Brunor to joust with Dagonet at his first tournament in order to deprive him of the honour of defeating a true knight.