Havent played to the end yet. So they are purebred sith?
It really doesnt fit into anything that is already continuous now that Legacy of the Force and the uh new thing 130 years later with Cade skywalker is established - there was no Sith army there under Darth Krayt, they used storm troopers.
As far as starwars is concerned right now Silri never came to power with her Sith army.
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