Little is known of the origin of Maalddor. It is believed he was born at the instant of creation of the other- dimensional universe in which he resided. In the billions of years that followed, the near omnipotent being wandered the universe doing all there was to do, following his every whim and curiosity. It was in his power to create life, yet he found more satisfaction in the destruction and subjugation of the universe about him.
Yet despite his power and his wanderings from one end of creation to the other, Maaldor failed to find the one thing that could make his existence palatable: challenge. In short, Maaldor was bored.
In the course of seeking out excitement in a life that included the conquest of the entire universe, he summoned Superman and Power Girl from their respective universes to engage him in battle, in the belief that they, two of the most powerful beings in the Multiverse, could provide him with the challenge he so craved.
Yet, even for these heroes of incredible power, Maaldor proved too strong. They might have perished in Maaldor's dimension if Superman hadn't been able to trick the Darklord into turning his awesome powers inwards onto himself to seek out the essence of his own evil. The results were disastrous to Maaldor, and in that instant, his phsical being collapsed in on itself, his cosmically formed life force imploding to create a new plane of existence, becoming the cosmic embodiment of Maaldor's insanity and evil, a universal intelligence of pure madness. Superman and Power Girl sealed the entry to this new dimensional plane so that its evil could never escape into the surrounding universes.
Maaldor, however, was not to be contained for long. Within months he had found a way to reach beyond his other dimensional boundaries, seeking out the mind of Superman in order to exact his revenge against the being who had sentenced him to an eternity of madness. Maaldor atempted to drive Superman insane, but with the help Madame Xanadu and a housewife and teenage boy also touched by Maaldor's evil, Superman was able to win out against the Darklord.
Maaldor reached out to Earth one final time, this time with a plea for help. With his madness causing the disintegration of his dark dimension, and threatening surrounding dimesions as well, Maaldor was going to die. The Phantom Stranger guided Superman and the Joker on a mission into Maaldor's mind, where the Man of Steel was able to perform a lobotomy, excising the diseased portion of the dimensional intelligence and stabilizingthe various dimensional planes.
The Darklord attempted one final conquest of this dimension when he discovered a near limitless source of power on the planet Oa, home of the Guardians of the Universe, and the Green Lantern Corps. The GL Corps were despatched accross the universe to halt the menace that had drained the mighty Battery of Power of its emerald energies. Maaldor was able to break through from his own dimension into this one. His victory would have been assured had not the Green Lantern Arkkis Chummuck sacrificed his own life in a last desperate attempt to reabsorb some of the energies Maaldor had stolen into his own body. Maaldor was then sent back to his own dimension by the rest of the GL Corps.
Maaldor the Darklord seemingly died on Oa at the hands of Krona during the Crisis on Infinite Earths.But Somehow Maaldor survived and encountered the fifth Starman