Pre-Crisis, the Materioptikon was a weapon designed by the villainous Doctor Destiny, who wielded it against the Justice League, creating illusions of a false world ruled by a fascist League. Its power was so great, it was able to start the forceful integration of Destiny's world into the real timeline. While defeated and separated from the Materioptikon, he was able to simply make another one out of his own dreams. When Destiny then proved he could continue doing this for as long as he could dream of the Materioptikon, the League then resorted to changing Destiny's mind so he could not dream at all, causing his transformation into the monster he later became.
Post-Crisis, the Dreamstone is one of twelve stones crafted by Dream of the Endless. The gem known as the Dream Ruby was the one that Dream poured the most of his essence into, making it is the most powerful of the twelve. The other known ones are a Rose-Quartz, which presumably became the Porpentine, a Fire Opal, a Black Pearl, a Topaz, and an Emerald, which was the least powerful of the stones. Some have been scattered, others destroyed.
When Dream was imprisoned, the Dreamstone passed into the hands of Doctor Destiny by means of his mother; Ethel Cripps had purloined it from one of her old lovers (one of the caretakers of Dream). Doctor Destiny changed it and tampered with it, forcing flaws in the stone and warping it with circuitry, so it would offer the totality of its power to him and no one else, including its former master, Dream. He also added more power to it, transforming it into the Materioptikon. After Dee was defeated and imprisoned in Arkham Asylum, the Justice League took the stone from him, storing it in a warehouse in upstate New York. Dee was able to escape Arkham and go after the stone following the death of his mother, Ethel Cripps.
Dream, after discovering the location of the ruby from Scott Free (New Earth) and J'onn J'onzz (New Earth), tried to repossess the stone, but was hurt, repulsed by the alterations Destiny had inflicted upon the Ruby. This allowed the escaped Doctor Destiny to take the stone and escape to an all night diner, where he took over the minds of everyone there, toying with them by showing them their ultimate nightmares, and ultimately causing them to murder each other. While this was happening, the reactivated Materioptikon/Dreamstone was wreaking havok on the entire world, causing erratic, violent behavior in ordinary citizens, an increase in murders and plane crashes, and general mayhem. The Justice League International was not available for comment regarding the chaos. When Dream, who had recovered from being incapacitated at the hands of the Dreamstone, arrived at the diner, Destiny destroyed the stone while trying to use it against Dream. He incorrectly believed that if he shattered it, Dream would die. Instead, the destruction of the stone released its infinite energies and re-empowered Dream, who proceeded to gently defeat Destiny, restore him to Arkham, and give him back his ability to dream.
However, Destiny was no fool, and by then had the knowledge to create another Materioptikon, one created for him, by him. However, it was heavily flawed; Destiny believed that if he managed to clear at least one full facet of the gemstone, he could use it as well as Morpheus' Dreamstone. While Destiny succeeded in forcing a confrontation between the JLA and him in the Dreamscape, he lost the gem, with his consciousness still trapped inside, to a petty loser named Darrin Profitt, who would use it and the gemstone's flaws in a ploy to dominate the world as the Red King.
It turned out each flaw in the Materioptikon represented an alternate, possible universe, each a terrible threat to the mainstream reality; by destroying each of the six and a half billion flaws, Destiny made it more likely he could eventually escape without damaging reality. Profitt, however, imprisoned Destiny and used these Parallels to forge a successful living by manipulating the stock markets by using the universes as testbeds for his market gambling, not caring about possible consequences. Bored with the pinnacle of wealth and admiration he had created for himself, he responded to a challenge issued by the captive Destiny to conquer the world. Using the gem's flaws, he convinced the greatest scientists on each to create immensely powerful technology easily capable of bringing down the Justice League. Arming himself with the armor and weaponry designed by these men, he became the Red King.
However, he was met with an unpleasant surprise: the four final flaws of the gem were the last, having destroyed all of the others in his ascent. Destiny believed he would lose, and he did, with a coalition of two Justice Leagues tricked him into destroying the gate to the final Parallel after releasing the imprisoned Destiny, leaving him stranded within an artifact he could not use or comprehend at the mercy of Destiny's released mind, who, understanding the Materioptikon like none other, prepared to start torturing Profitt with the powers of the complete Materioptikon. Thus, Profitt forever lost the chance to integrate any of his upgraded selves into the mainstream reality with the Materioptikon, and Destiny, while still imprisoned, now has in his dreamself's hands a fully powered Materioptikon capable of ranking against the Dream King's.
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