Darth Mobius

Darth Mobius is the sith lord who first formed the Sith Empire over 35 Thousand years ago. He ruled the empire with his apprentice, Darth Vexus until around 7000 Years later, when another sith lord sealed Mobius on a temple on the frozen world of Ilum, where he remained until Jedi Master Yoda and Ahsoka Tano discovered him by accident.