Sometime during his reign Darth Rivan made a Sith holocron, which later fell into the hands of the Imperial Inquisitor Valin Draco.
Darth Rivan, a brilliant Zelosian, was known for many other galaxy wide contributions. He made a base on Almas, and modified the atmosphere so it could be inhabitable. He also created the Sith battlelords and was made famous for being the wielder of the powerful artifact known as the Darkstaff, a semi-sentient weapon capable of draining Force-essence from a living being.