the compilations of both revan and the exile are hard to explain, they both werent ordinary jedi/sith they where a completely different breed. the exile, at first, was a force user of average ability. he demonstrated an unusual ability to easily form connections with others, forming bonds through the force that allowed him to leech off of his followers, though he was largely unaware of this ability. after reconnecting with the force, the ability became even stronger. he was able to gain greater power through all the deaths he caused, a result of his being a "wound" in the force, but again he was largely unaware of it.
the exile was one of only three known Force users to voluntarily sever himself from the force
this is part of wookiepedia "At some point during the war, Revan was scouting for bases along the Outer Rim when he learned of Malachor V, a planet that the Mandalorians were