One of the knights drew his sword to kill it, and this unexpected movement proved the signal for one of the bloodiest battles described in mediaeval poetry.
"An addere crept forth of a bushe, Stunge one o' th' king's knightes on the knee.
Alacke! it was a woefulle chance, As ever was in Christientie; When the knighte founde him wounded sore, And sawe the wild worme hanginge there, His sworde he from the scabbarde drewe; A piteous case, as ye shall heare; For when the two hostes saw the sworde, They joyned in battayle instantlye; Till of so manye noble knightes, On one side there was left but three." _King Arthur's Death_.
[Sidenote: Arthur wounded.] On both sides the knights fought with the utmost courage, and when nearly all were slain, Arthur encountered the traitor Mordred.

Summoning all his strength, the exhausted king finally slew the usurper, who, in dying, dealt Arthur a mortal blow.

This would never have occurred, however, had not Morgana the fay, Arthur's sister, purloined his magic scabbard and substituted another.

All the enemy's host had perished, and of Arthur's noble army only one man remained alive, Sir Bedivere, a knight of the Round Table.

He hastened to the side of his fallen master, who in faltering accents now bade him take the brand Excalibur, cast it far from him into the waters of the lake, and return to report what he should see.