Darth Rivan
this ancient Sith Lord built a fortress on the planet Almas, despite its inhospitable atmosphere. He created the kaluthin grass to modify the planet's landscape and atmosphere, and managed to survive for many decades on the planet before being driven off Almas by the Jedi Knights during the Sith Wars. He later perished in the Battle of Ruusan. Analysis of the fortress performed shortly after the Battle of Naboo revealed that the dome on the fortress was well over 1,000 years old, indicating that Rivan himself was of a very advanced age at the time of its construction. This led many Jedi scholars to believe that Rivan was not of human origin.