He and his brother, Sir Gherard le Breuse (Gerard), were a murderous pair who “guarded” a passage of the water of Mortaise (Marcoisa) as an excuse to kill passing knights.
Gareth slew them both on his way with Lynette to Castle Dangerous, to defeat the Red Knight of the Red Lands. This was Gareth’s first conquest, not counting Sir Kay.
Source
Le Morte Darthur | Sir Thomas Malory, 1469-1470
