Dude, Darth Nihilus had a reputation for killing entire populations of systems by draining the living Force energy from their bodies. Only one person survived these planet drainings because he willed it so. He figured out how to survive by embedding his soul into his robes and mask (which still survived for centuries so he technically lived on after his apparent death). He was one of the few sith to earn a title based on his ability. What was Vader lord of? What was Revan lord of? Nihilus earned the title Lord of Hunger. He is easily one of (if not the greatest) sith who ever lived and could carry out feats of the Force that would never be seen or repeated by anyone ever again.