King Arthur and King Cornwall

[The opening section of the poem is missing and the rest of the text is heavily mutilated]. Arthur boasts to Gawain about his Round Table, but Guinevere replies that she knows a better one, which stands in a palace worth more than his whole kingdom of Little Britain. When she refuses to reveal its location, Arthur vows to seek it. He and four knights – Gawain, Murramiles, Tristrem and Bredbeddle (the Green Knight) – dress as pilgrims and travel far and wide until they arrive at a castle. A porter, dressed entirely in gold, informs them that it belongs to King Cornwall, the richest man in Christendom. Arthur asks for a night's lodging, [and the disguised knights are brought before Cornwall]. Suspecting that they come from Britain, the king boasts that he has fathered a beautiful daughter with Arthur's wife. He also boasts of a miraculous horse, and other magical items which are better than any in Arthur's court: a horn, a sword and a powerful sprite called Burlow Beanie.

Arthur and his knights retire to bed, and Cornwall's household conceal Burlow Beanie in their chamber to spy on them. Arthur vows to kill his rival before returning home, while Gawain pledges to carry off his daughter. They discover the sprite, which has seven heads and breathes fire. Sir Bredbeddle fights the sprite and all his weapons break, but he finally subdues it with the help of a holy book that he found by the seaside. Burlow Beanie agrees to obey him and Sir Bredbeddle orders the sprite to bring forth Cornwall's horse. Sir Murramiles attempts to ride it, but is unable to make it move. On Bredbeddle's orders, Burlow Beanie fetches the golden wand that controls the horse, as well as the other magical items, including Cornwall's horn, which he shows them how to use. Bredbeddle presents Cornwall's sword to Arthur, who uses it to cut off his rival's head. Sir Gawain abducts Cornwall's daughter and the knights return to Little Britain.

Edition used for plot summary: Hahn, Sir Gawain (1995).