He is a former slave who had dedicated his life to turning his masters’ lives into a nightmare. Once, he burned down the whole camp of a mare who wanted him to be her f*cktoy. Later, he poisoned his another owner. One by one, his masters were dying in horrific ways - even for the wastelands.
Free at last, Bloodshot decided to leave the life of a slave behind, to start a new chapter… which was slavery from the other side of a leash. He was a good master, though, who punished the workers more severely than the slaves. However, suddenly, he looked at the scars under his bandana - the scars from a collar. He suddenly realized that he became one of his own personal enemies - a slaver. The nightmares about his past were constantly haunting him, not letting him sleep for more than a moment.
Ultimately, he decided to “retire”. He left the slavers, but he returned after some time, armed to teeth, and went postal on them, leaving not a single pony alive. That was the time whem he declared war to every single slaver on the wasteland. He would bring them to hell himself…