Dark One's Dagger

The Dark One's Dagger is a magical item featured. It first appears in the fifteenth episode of the first season. The Dark One's Dagger originates from the severed blade tip of Excalibur.

Trivia

 * The dagger originated in Camelot and was created by Merlin.
 * According to Cora, if the Dark One is killed without the use of the dagger, he or she will expel the powers of the Dark One into the air after death without anyone else being next in line to inherit it.