Darth Ebolus

Darth Ebolus (birth name Tyret Wenhyr) was a Sith Lord who survived the Seventh Battle of Ruusan after discovering Darth Bane's plan to eliminate the Brotherhood of Darkness. He was born on Tatooine around the year 1021 BBY. His parents were murdered by Republic troops after Tyret and his father received a large amount of credits from selling parts of a Krayt dragon. Tyret captured the troops and tortured them for days before finally killing them. He then hitched a transport off the planet, taking only the credits and his father's necklace, which was the Wenhyr family crest.

After killing the Republic troops, Tyret joined the Sith as a soldier. He fought as a grunt for around 6 months before being discovered to be force sensitive. He was sent to the academy on Korriban to train under Lord Kopecz. He was offered the chance to change his name but declined, hoping to keep the memory of his family alive; but after discovering that the ancient Sith rune for the word Ebolus or virus resembled his family crest, he decided that that would be a more appropriate name, as he called himself a virus and blamed himself for his parent's deaths. He took to wearing a white mask that had the rune on the forehead, he changed the marking on the mask over time to match the Sith tattoos he got on his face

Ebolus, as he was now known, quietly trained in the background, while Bane was becoming a promising student. Like Bane, Ebolus spent much of his time in the library of the Temple, learning much about the ancient Sith and their language. Eventually, the Korriban Academy was sent to Ruusan to reenforce the Sith forces fighting the Jedi. He eventually overheard Bane tell Qordis of his plan and then kill Qordis. Ebolus considered killing Bane, but reasoned that Bane was a better fighter and he had some good ideas about the reformation of the Sith. Taking these things into account, Ebolus stole a Sith fighter craft and left the planet.