Star Wars: The Clone Wars - The Nightsisters Trilogy(2010)

Overview:

For the first time ever, Sith training will be explored, and with it, truths about the very nature of the dark side itself! A warrior forged by a dark sorcery as mystical and powerful as the Force, Opress will uncover shocking revelations about the galaxy’s tenuous balance of power, including secrets about one of the Sith’s most infamous villains Darth Maul! From his origins to his fate, Maul’s mysteries will at long last be uncovered!