Carnwennan is Morgan's dagger. She was gifted it by Merlin when she was only a baby. It was known to have magical powers.
Lady Nimue stands by and watches her people starting to parish because of a dark and powerful force arisen in England. She forges the dagger, Carnwennan and uses it to defeat the evil source for good. She stores the dark powers of the Dark Lord inside a temple and also hid the sword in the city that would become Camelot. She eventually gives the dagger to Merlin, who givers it to his friend Uther's daughter, Princess Morgana.
she kept hidden in her boot when she and Arthur went alone into the woods. She held it on her person at all times, even when she never needed it and only brought it in case of emergencies. Morgan also used it to chisel a wood while she and Arthur went to be taught by Merlin.
One day, the dark lord returns and Morgan sets out on the quest to find the long-lost sword. With help from her step-brother, Kay, and several of the knights, Morgan uses it to defeat the darkness in the sequel.
- In original legends , Carnwennan was not Morgan's dagger, but her half-brother, Arthur's.