Thus Sir Lancelot rode so far into the land that he came nigh to the place where he had heard that the fearful beast had made its lair. There did he see many a helm, and spear, and weapon of the knights it had slain, whose bones lay there stripped of flesh, which the monster had devoured; he might well be afraid! So soon as Lancelot might know where the beast was wont to lie, he made haste thitherward, and so soon as it was ware of his coming it came flying in such guise as it had been the Devil, and set upon Sir Lancelot straightway. It feared neither sword nor spear, nor armour, nor might of man. And Lancelot smote at the monster so that his spear brake in twain, yet had he not bruised it a whit, or pierced its hide; then he drew forth his sword and smote with great force, but he harmed it not, and it seized Lancelot by the throat and scored him in such wise that the knight was wroth thereof, for it tare a great rent through the hauberk even to the flesh, and wounded him sore. Many a time did Sir Lancelot strike and smite at the beast, but never a groat might he harm it; but the monster fell upon Sir Lancelot and scored him even to the feet, and dealt him many a wound, and breathed out venom upon him; had it not been for a ring which Sir Lancelot ware upon his finger he had fallen dead where he stood from the poison. Then the monster sprang towards him with gaping jaws, as it were fain to swallow him, and Lancelot watched his chance, and thrust his sword into its mouth, and clave the heart in sunder, and the beast gave a cry so terrible that 'twas heard a good two mile off.
Then the traitor who spied all from afar, when he heard the cry delayed not, but rode swiftly towards the lair, for he knew well from the cry that the monster was slain. When he came to the place he found Sir Lancelot sitting, binding up his wounds, which were many and deep. The knight began to bemoan his plight, and went towards him saying that he would bind his wounds for him. That cowardly and wicked knight, he came even to Sir Lancelot's side, and snatched stealthily at his sword, and sprang backward and smote at him, wounding him so that he fell as one dead.
When the false traitor saw this he deemed that he was dead, and left him lying, and went there, where the monster lay, and smote off the right foot, thinking to take it to the maiden of whom I have told ye, that he might therewith win her to wife.