James Crookshank

James Crookshank, sometimes referred to as Sheriff, is a human cowboy living on the western themed planet, Shimmerwater. He was the most powerful and undisputed leader of Shimmerwater, he also served as the leader of the largest gang at the time, the Gunmen of the Apocolypse (GOTA). 
Crookshank was considered the deadliest hitman in the galaxy, with a feared reputation. This stemming from him holding the power of Inexistence, one of the Nine Continuance. He suffered a fall from grace sometime between 2198 and 2201, after Xerxes, a Deathslinger, who was on a mission nearby, challenged Crookshank. Xerxes, using his Deathslinger abilities, was able to best Crookshank and somehow steal the power of Inexistence. Without his trump card, and despite still being a powerful shooter, Crookshank lost his position to the more powerful members of his gang. 
He went into seclusion on Shimmerwater, hoping to live out the remainder of his life in peace.