Who is Darth Malgus

Malgus was a sith lord that more less ruled the sith and then fell. Currently in the swtor universe, I'm not sure what he's doing but based off the cinematic, I'm guessing he's trying to reforge the sith empire with an ancient map. Trying to find force users that wearnt picked to be jedi.

People can dislike other media of star wars but he's coming regardless