Having been referenced in Revenge of the Sith as the powerful Sith master of Darth Sidious himself, the origins of Palpatine's teacher and his legendary abilities have largely been left a mystery ...

Among them, people speculated that At Attin could be part of a secret Sith cult led from the shadows ... and the Sith Lord publicly known as Sheev Palpatine, though, and that is hinted at when ...