Morgan Le Fay
Morgan Le Fay was a mythological figure in Arthurian legend. Morgan Le Fay the daughter of Igraine, the mother of Arthur Pendragon and her first husband Gorlois, the King of Cornwell. As such she was the half sister of Arthur Pendragon. She became a sorceress under the tutelage of Merlin. Later Morgan Le Fay used the same magic that Merlin used on Urthur Pendragon to help him seduce Igraine, in order to seduce her half brother. After their night together she gave birth to Mordred, who would go on to kill King Arthur at the Battle of Camlann.