Traveler

Traveler Person from an advanced civilization takes an advanced combat suit capable of stealth and invisibility, superfast speed and reflexes, goes to a planet in another dimension using a ship, and attacks/captures various medieval despots and tyrants. He places their brains and spinal column inside torture devices he's created himself, which keep the brain alive but constantly apply shocks to the spinal column. They are stored inside the dimension traveling ship. Another group of people are tasked with tracking him down and stopping him, and take a similar ship to the other dimension's planet. The story follows the cat-and-mouse chase between the antagonist and the group tasked with capturing him, and the results of their effects on the alternate world. The second part of the story involves the tyrannical dictators, who have been recovered and had their brains placed into identical looking android bodies. The non-interference clause prevents them from going back. Also, their bodies cannot consume food and must live off of charging stations, which their home doesn't have. Unable to return, they must start new lives in an advanced civilization that they have little understanding of. King 1: Has amnesia/mental issues stemming from damage to his brain that occured some time between being kidnapped and freed. King 2: Learns to pilot, steals a ship and flies back to his home planet, with the intention of dying to atone for his past behavior. King 3: Finds out the location of the prison where the person is being held, intentionally gets himself arrested near said prison, finds the person and kills him in prison. King 4: Is obsessed with a love interest he had back on his home world and goes mad, drawing thousands of pictures of her in solitude. King 5: Fully embraces his new life and becomes somewhat of a celebrity, his true aim is to gain power through these methods. King 6: Becomes bored with the mundane, relatively peaceful life he's been placed in and becomes involved in organized crime and violence. King 7: His brain was destroyed during the capture and recovery operation. Permanently killed at that point.