Vergere (pronounced /vɚ’ʒɪɹ/) was a Fosh Jedi Knight turned Sith in the waning years of the Galactic Republic. She was the former Padawan of Jedi Master Thracia Cho Leem and disappeared in 30 BBY, finding the Yuuzhan Vong on Zonama Sekot and secretly living with them for half a century.
During the time of the Yuuzhan Vong invasion, Vergere reappeared and tortured Jacen Solo, wanting to turn him into a future Sith apprentice. She was hunted by the New Republic and hid herself, helping Warmaster Tsavong Lah and other Yuuzhan Vong as well as Solo. At the climactic Battle of Ebaq 9, she returned to the light side of the Force and sacrificed herself, killing many Yuuzhan Vong to save Solo.
By 40 ABY, the Sith revealed that Vergere had also, secretly, been one of them. Eventually, Vergere’s training helped turn Jacen into Darth Caedus, the Dark Lord of the Sith.