Yezzil

Yezzil the Raging Storm was a female Human Sith living during or after the Cold War.

Behind the scenes
Yezzil the Raging Storm was added to Star Wars: The Old Republic with Knights of the Eternal Throne expansion as a World Boss for Dark vs. Light system. Whenever Dark side of the Force reaches victory state on a server, Yezzil the Raging Storm has a chance to spawn at one or more of selected locations on Coruscant and Dromund Kaas alongside other Dark Side World Bosses. Though killing her is required for an in-game achievement, it is impossible the year and the planet where her death took place.