Madame Xanadu was published by DC Comics.

Madame Xanadu was the sorceress Nimue who cast a spell on Merlin. Merlin had the last laugh, though, as he succeeded in stripping her magic away from her. She wandered for some time before deciding that she wanted to atone for her sins. She did so by helping those troubled with the supernatural. Xanadu is descended from Gypsies, but has operated her fortune telling parlour out of Greenwich Village for years. She was later able to gain her immortality by besting Death in a game of cards. She however remained without any real magic might of her own, which has led her to manipulate various forces in order to gain power.