Darth Plagueis

Darth Plagueis was a Sith Lord who was rumoured to save the ones dear to him from death. He loved his apprentice like the son he never had. His apprentice was Darth Sidious aka Palpatine. He formed a plan in which he and Sidious would rule the galaxy as equals. Sidious however took a secret apprentice ,Darth Maul ,and killed his master in his sleep. He was to appear as a spirit and villain along fellow Sith and Imperial Overlord Darth Vader and would have been a boss. At one point he was alive and Vader would have sent Starkiller to find Plagueis, so Vader can bring his wife back from the dead. At another point Starkiller was a reincarnation of Plagueis ,but Plagueis was ultimately scrapped as the team thought that it would be difficult to bring the Sith Lord in the game. He was a human at one point as seen in some sketches and was later changed to a Muun in the last sketches, before being confirmed that his species was indeed the Muuns. In all sketches he has a Sith cloak.