One of the most interesting additions to the Swamp Thing cast of characters is without a doubt Madame Xanadu, one of the most prominent mystic beings of the entire DC Universe. Portrayed by Jeryl Prescott, she’s spotted in Pilot on the upper floor of the (single) bar of Marais, that Abby Arcane is showing to Alec Holland, and Abby wonders how the woman is even still alive. In the comics, Xanadu is immortal, so not much mystery about that. The show’s version is remarkably older than the original (at least, older-looking), and also her ethnics has been changed. The character is among the many heroes set to appear in the long-awaited Justice League Dark by Guillermo Del Toro, but the film is still in development hell, and maybe we’ll never get to watch it. At least, we have this one live action portrayal of the character. And the original one, of course.
Nimue Inwudu was an ancient sorceress, daughter of Atheron and Staegys, two of the last survivors of Atlantis. She had two sisters, Morgaine Le Fay and Vivienne the Lady of the Lake, all three powerful magic users. The destiny of the three sisters was deeply connected to the fabled realm of Camelot, and Nimue was for a time also the lover of Merlin, the court wizard. The mystic being known as the Phantom Stranger, though, tricked Nimue into believing that Merlin had been manipulating history and the fallen Camelot itself for his own personal gain, so she betrayed him and imprisoned him for centuries… but the wizard, in turn, stripped her of all her magic, as well as of her 
immortality. In order to stay alive, Nimue had to use potions, but her lack of powers didn’t prevent her from trying to guide history, putting what little remained of her magic (mainly fortune telling) and her wisdom to the service of powerful men and women throughout history. In the XIII Century, she traveled to the Mongol Empire, where she became the adviser of Kublai Khan; she fell so much in love with the city of Xanadu that she decided to adopt its name, becoming Madame Xanadu. Thanks to her potions she crossed centuries, and she was in Spain during the XV Century, entering in conflict with the Spanish Inquisition due to a lesbian relation she was having at the time. She was in France at the end of the XVIII Century: she even tried to advise Queen Marie Antoinette just before the French Revolution, but the queen didn’t listen to her, caused an uprising, and was executed by the rebels. Xanadu, however, gained a personal victory: while she was in Versaille, she met Death of the Endless, and challenged her to a card game. Her centuries-long experience allowed her to gain the upper hand, and she won the prize: she regained her immortality (just in time, as the Revolution in the meanwhile had become quite a brutal and bloody mess). Finally, in the 1940s, she met a powerful magician, John Zatara, with whom she started a passionate relationship with: of course, she had some plans in mind for him as well.
Madame Xanadu had foreseen the birth of the Spectre, an enormously powerful being born from the fusion of a mortal and of the angel Aztar, that she hoped to control for her own purposes; the Phantom Stranger, of course, would have meddled with the being’s birth, so Xanadu manipulated Zatara into sealing him, thus letting P.I. Jim Corrigan become the host of Aztar. Her following visions, though, showed to her that she had unleashed a terrible threat on the world, as the Spectre was impossible to control, and he would have brought catastrophic destruction over all the planes of reality. In order to try and atone to her (many) past sins, Madame Xanadu opened a fortune parlor in 
Greenwich Village, where she offered her assistance to anybody having troubles with the supernatural. She couldn’t intervene directly in the matters (either because she couldn’t, or because she didn’t want to, or else because some other force prevented her to), but she gave precious advises to solve whatever problem her clients had, and when the mystic being causing trouble was properly defeated and caught, she imprisoned it in one of her jars, keeping it locked in her parlor. In the meanwhile, the Spectre did what she had foreseen, and went into a rampage… but was destroyed by the Anti-Monitor during the Crisis on Infinite Earths. For the first time, Madame Xanadu used the magic relics she kept in her parlor to bring the Spectre back to existence, but this time she didn’t want to use his power for herself: she acted as an adviser to his human part, Jim Corrigan, eventually falling in love with him. Using her unique influence over Corrigan, Xanadu stopped many rampages of the Spectre, eventually managing to save Jim’s soul, always one step behind his own redemption, protecting him even from the seduction of a demon such as Neron. After helping the Spectre, Madame Xanadu became a reference point for the superhuman community: the Suicide Squad, John Constantine, Deadman, Mary Marvel, Zatanna, Dr. Mist… eventually, everybody who ever dealt with the supernatural came to her, and she was always happy to lend a hand.
Nimue Inwudu is a wise and highly intelligent woman, characterized by a sarcastic and mean nature that she can’t hide even behind the (honest) intention to help others in order to redeem her soul. As Madame Xanadu, she’s a powerful sorceress, but after Merlin’s curse she has access only to a fraction of her original powers: she can see the future, which she interprets with tarots, she can teleport and move things with her mind, she can levitate, and she’s immortal and invulnerable, unkillable by any means; she possesses a number of mystic relics and magic books, as well as weird imprisoned creatures and demons, that she can use to perform more powerful spells. Blind, yet all-seeing, Madame Xanadu is the witness of human history, a homo magi who crossed centuries and who’s ready to share her knowledge with whoever needs it… all this to amend the fact that she put all reality in jeopardy because of her lust for power.
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