Oraku is a villain in Aftermath. He first appeared in season 8, being mentioned by XereX. He is scheduled to appear multiple times in the season, being the main antagonist.
Oraku's goal is to revive The Dark Lord. His method of doing so is simple, but difficult to pull off. Oraku plans to create an alternate dimension where The Dark Lord defeated the Toa Zehvor, and create a portal to that alternate universe which could be used to bring TDL back. However, the plan won't work unless he finds someone who has a memory of the battle itself, since the alternate dimension has to be based off something.
To deal with that, he sent XereX to capture Brenmac...