Lastrix Vell was a Sith Lord who lived in the years which followed the Great Force War. Lastrix grew strong in the Force and eventually slew her Master and took his title. When the Sith Civil War began, Lastrix emerged as one of the two leading Sith, forming the Nyhlus Fanction based upon finding ancient Sith Knowledge in order to restore the Empire's former glory.
cool fig! and btw the sith species never went totally extinct. the purebloods were mostly breed out by 5000 BBY but there were still some who didnt interbreed. and in SWTOR you can play as a sith pureblood. and SWTOR is around 3000 BBY right?