Darth Tenebrous was a Bith Sith Lord, and master to Darth Plagueis. He had a very rational
approach to his use of the Force which he viewed as a tool rather than a mystical energy
field that could shape the galaxy. He served as the apprentice to a Twi’Lek master, who
he killed in accordance with the Rule of Two.
Publically, Tenebrous was known as Rugess Nome, a celebrated designer of high-class
starships. His status gave him the power to manipulate the meeting and marriage of two
Muuns, knowing that their child would be strong in the Force. His plan worked, and when the
child reached the age of five, Tenebrous took him from his parents, made him his apprentice,
and named him Darth Plagueis.
For decades, Plagueis learned the ways of the Dark Side as well as science from his
master as they furthered the Sith’s Grand Plan set in motion by Darth Bane. While on
a remote planet in search of a cortosis mine, Plagueis saw his chance to end his master’s
Unbeknownst to Plagueis, Tenebrous had engineered a retrovirus that allowed him to manifest
his consciousness within his midichlorians. As his body died, he used the tiny organisms
to infest his apprentice, and remove Plagueis’s ability to sense the future, which would one
day allow Darth Sidious to murder him in his sleep.
Exiting Plagueis’s body, Tenebrous’s consciousness saw his own ancient, mummified remains. The
retrovirus had somehow mutated, and caused him to relive the final moments of his life
over and over, seemingly for all eternity.