well, i'm still trying to figure out the origin of her power, though being that madame xanadu is super old it might come down to either that or some sort of familial lineage. i haven't quite decided yet. she's been in new york for a handful of years, probably running a small occult space where she can provide tarot readings to the public. with her cards, she draws most of her precognitive powers, though she can't interfere with people's strife. she can only advise them how to proceed. her deck of cards is old and some would say they hold their own power that aids her. she's obviously proficient in spells despite the occasional accident or hiccup. i think that's part of the reason why she prefers to be alone. throughout her travels she has come into an artifact here or there to add to her collection and keep safe from forces that might use it for destruction. see? she's not bad, even if she's followed her own agenda rather than sticking to a moral code.