The Red King is a villain in the DC comics.
Darrin Profitt spent most of his life taking up space. He was perfectly average in the worst possible way. Though he had lofty goals and dreams, but nothing he ever acted on because, to Profitt, the risk in succeeding always came hand-in-hand with the possibility of failure, at least until he just happened to be one of six billion innocent bystanders in the dreamscape during a battle between the Justice League and Doctor Destiny. After the defeat of Doctor Destiny on the dreamplane, the Materioptikon gem on his chest sucks him inside and falls at the feet of Darrin Profitt's dreamself. Profitt discovers that the gem is in his possession, and is accidentally sucked inside the artifact where he meets Doctor Destiny's trapped consciousness. According to Doctor Destiny, the Materioptikon has the ability to reshape reality, but it is flawed, anyone who enters the gem automatically generates multiple physical copies from multiple possible universes, splitting that person up among these universes.
Also according to Doctor Destiny space and time was never meant to do this, using the gem in this fashion threatens the spacetime continuum. Destiny created special tools that re-integrate his own multiples and those of anyone else who enters the gem. In order to return to the real world without damaging reality, and generating any more dangerous alternate universes, Destiny stated that he had to repair all six billion flaws in the gem. Every time he repaired a flaw, he destroyed one of many possible universes and in all of them his body remained catatonic and dreaming in Arkham Asylum. Profitt, seeing the Materioptikon as the ultimate no-lose solution, overpowers Destiny and traps him in a facet of the gem, which he then used in a way Doctor Destiny never dreamed of to become the undisputed master of every possible outcome. Fame, fortune, and influence are just starting points for greater things, stepping stones that transform Profitt into the most powerful meta-human on the planet, the Red King.
Profitt creates a few duplicates of himself using Doctor Destiny's tools and sends them out to place a bet at the race track and then invest that money in stocks, both the winners and losers return to the gem and report their results, he then uses the favorable results in his own reality. According to Doctor Destiny he endangered all of reality, all of Space and Time so that he could win a bet at the track. Darrin uses the parallels to create favorable outcomes one by sending his duplicates into a Parallel to test for a specific outcome, if they failed he deletes that Parallel, if they succeed he uses their solution. Darrin used the billions he'd made from manipulating the stock market via the Parallels to become a billionaire philanthropist and playboy. In response to a challenge posed by Doctor Destiny, he has used Parallels to acquire technology that can defeat the Justice League and conquer the world.
Profitt created three Parallels; the first where the Red King became a member of the Justice League after defeating newly empowered version of the Royal Flush Gang on two separate occasions and even having a romantic relationship with Wonder Woman; the second where he demanded for the unconditional surrender of Earth by threatening the use of a Doomsday device that would destroy the planet, but only for the device to be prematurely activated and forcing a mass planetary evacuation to Mars; the third where the Red King used his unaccounted powers and killed the Justice League, but at the cost of devastating Earth.
Unfortunately for Profitt, his misuse of the Parallels becomes his own undoing when the Second Parallel version of the Justice League learned the truth of their existence as a facet in the Materioptikon and sent their reality's Plastic Man to the core reality to communicate with their selves in there to do battle with that reality's Red King. This Plastic Man ended in the First Parallel after releasing Doctor Destiny in the hub world of the Materioptikon, where he posed as a bomb similar to the one which destroyed the Earth in the Second Parallel. The Red King from the Third Parallel traveled to the First Parallel after erasing his reality and forcefully merged with the native Red King. Profitt was then cornered at the Justice League Watchtower, where he was duped into believing the bomb would kill him if he could not defeat the entire Justice League in under a minute, and trapped within the core reality's Materioptikon after Wonder Woman crushed the stone, destroying the link between the final Parallel and the Materioptikon. Within the Materioptikon, Doctor Destiny's dreamself roamed freed and prepares to torture the Red King with his now omnipotent powers, having sealed all of the gem's flaws and completing it as the true Materioptikon.