Book X - Chapter LXIX - How Sir Tristram was unhorsed and smitten down by Sir Launcelot, and after that Sir Tristram smote down King Arthur.
THEN was the cry of heralds and all manner of common people: The Green Knight hath done marvellously, and beaten all them of Orkney. And there the heralds numbered that Sir Tristram that sat upon the black horse had smitten down with spears and swords thirty knights; and Sir Palomides had smitten down twenty knights, and the most part of these fifty knights were of the house of King Arthur, and proved knights. So God me help, said Arthur unto Sir Launcelot, this is a great shame to us to see four knights beat so many knights of mine; and therefore make you ready, for we will have ado with them. Sir, said Launcelot, wit ye well that there are two passing good knights, and great worship were it not to us now to have ado with them, for they have this day sore travailed. As for that, said Arthur, I will be avenged; and therefore take with you Sir Bleoberis and Sir Ector, and I will be the fourth, said Arthur. Sir, said Launcelot, ye shall find me ready, and my brother Sir Ector, and my cousin Sir Bleoberis. And so when they were ready and on horseback: Now choose, said Sir Arthur unto Sir Launcelot, with whom that ye will encounter withal. Sir, said Launcelot, I will meet with the green knight upon the black horse, that was Sir Tristram; and my cousin Sir Bleoberis shall match the green knight upon the white horse, that was Sir Palomides; and my brother Sir Ector shall match with the green knight upon the white horse, that was Sir Gareth. Then must I, said Sir Arthur, have ado with the green knight upon the grisled horse, and that was Sir Dinadan. Now every man take heed to his fellow, said Sir Launcelot. And so they trotted on together, and there encountered Sir Launcelot against Sir Tristram. So Sir Launcelot smote Sir Tristram so sore upon the shield that he bare horse and man to the earth; but Sir Launcelot weened that it had been Sir Palomides, and so he passed forth. And then Sir Bleoberis encountered with Sir Palomides, and he smote him so hard upon the shield that Sir Palomides and his white horse rustled to the earth. Then Sir Ector de Maris smote Sir Gareth so hard that down he fell off his horse. And the noble King Arthur encountered with Sir Dinadan, and he smote him quite from his saddle. And then the noise turned awhile how the green knights were slain down.
When the King of Northgalis saw that Sir Tristram had a fall, then he remembered him how great deeds of arms Sir Tristram had done. Then he made ready many knights, for the custom and cry was such, that what knight were smitten down, and might not be horsed again by his fellows, outher by his own strength, that as that day he should be prisoner unto the party that had smitten him down. So came in the King of Northgalis, and he rode straight unto Sir Tristram; and when he came nigh him he alighted down suddenly and betook Sir Tristram his horse, and said thus: Noble knight, I know thee not of what country that thou art, but for the noble deeds that thou hast done this day take there my horse, and let me do as well I may; for, as Jesu me help, thou art better worthy to have mine horse than I myself. Gramercy, said Sir Tristram, and if I may I shall quite you: look that ye go not far from us, and as I suppose, I shall win you another horse. And therewith Sir Tristram mounted upon his horse, and there he met with King Arthur, and he gave him such a buffet upon the helm with his sword that King Arthur had no power to keep his saddle. And then Sir Tristram gave the King of Northgalis King Arthur's horse: then was there great press about King Arthur for to horse him again; but Sir Palomides would not suffer King Arthur to be horsed again, but ever Sir Palomides smote on the right hand and on the left hand mightily as a noble knight. And this meanwhile Sir Tristram rode through the thickest of the press, and smote down knights on the right hand and on the left hand, and raced off helms, and so passed forth unto his pavilions, and left Sir Palomides on foot; and Sir Tristram changed his horse and disguised himself all in red, horse and harness.