Aurach is an Erinyes Baatezu, one of the Lawful Evil Outsiders from the Nine Hells of Baator. Puzzlingly, rather than abide by her Lawful nature and serve her masters in the Blood War or the neverending quest for mortal souls, Aurach fled Baator and made her home in the Automata Underground.

She is one of the three members of the original Council of Anarchy, but just prior to the attack by the Bladeling mercenaries, she mysteriously vanished. Rumors circulate about whether she was in on the attack, whether she was kidnapped, or simply caught wind of the attack and fled without telling anybody. Either way, Aurach was the most physically and magically powerful member of the Council of Anarchy, and without her support the Underground quickly fell.

Leggis Scrogg continued to hunt for information on her whereabouts, and decided to leave her seat on the Council of Anarchy open until she either returned, or was confirmed dead.

The party discovered that her wings had been sold to a rich family and grafted onto their son's back. Upon infiltration of the family's residence, they learned that the Black Lotus had sold the family the wings, from a location in Torch. After defeating the Black Lotus and their accomplices in Torch (The Gray Orb), they recovered Aurach from a Dungeon under the Gray Orb headquarters. (12,13,18,19,20)