Nekron is the embodiment and manifested form of death and pure darkness.
Ruler of the Dead Zone, a dimension that all spirits pass through on their way to their final resting places (be it Hell, Heaven, Tartarus, Purgatory or any other realm of the afterlife), Nekron has the power to take and restore life as he pleases and can control spirits of the dead, undead or once-dead (resurrected). He is described as the most powerful dark force in the DC Universe.
Before sentience, existence was said to have been at peace in the form of the Darkness of Death (also known as "The Black"), however, the rise of the White Light of Life and the later shattering of the White Light into the Emotional Spectrum led to an imbalance that the Darkness sought to correct by creating Nekron to return existence to its original state of Darkness. While initially unleashed upon the universe, Nekron was confronted and defeated by the Guardians of the Universe; who at the time wielded the White Light of Life.
Unable to return to the living universe, Nekron came to be the ruler of a dimension that adjoined all of the realms of the afterlife. Entrapped within this dimension, he sought to increase his power to free himself and return to consume all life within existence.
While waiting for the coming of the "Blackest Night"; a prophecy that foretold the return of "The Black", Nekron encountered the banished energy of Krona whose presence within the Realm of the Dead created a paradox due to an immortal now residing within the Realm of the Dead. This paradox created a rift between the dimensions of life and death through which Nekron gazed into the universe and saw the land of the living once again. Resurrecting Krona, he imbued the Maltusian with great power and returned him to the land of the living with an army of undead spirits with the goal of killing other immortal Maltusians, which would send them to the land of the dead and increase the paradox rift; allowing Nekron to return to the land of the living.
Krona and his army confronted the Green Lantern Corps and successfully killed several of the Guardians of the Universe, also destroying the Green Lantern Central Power Battery in the process. However, Green Lantern (Hal Jordan) of Earth managed to rally his comrades into attacking Krona with the remaining energy and journeyed into the Realm of the Dead where he also incited the spirits of the deceased Lanterns into rebelling against Nekron. With Nekron's attention divided, the remaining Guardians were given enough time to successfully imprison Krona and close the rift; preventing Nekron from escaping his realm.
Now aware of other opportunities to enter the living world, Nekron remained vigilant for other chances to escape his realm. He eventually saw another chance to do so when he sent the spirit of Angela Adam to haunt the dreams of her husband, Nathaniel Adam. By doing so, Nekron arranged for Adam to be brought to the Realm of the Dead via the astral plane on the premise that he could meet his dead wife. In reality, as Nathaniel was linked to the Quantum Field, Nekron intended to take the hero's soul and use it to pull the Quantum Field into his own realm; thereby dragging every living creature into the realm of the dead. However, Nathaniel caught on to Nekron's plan and absorbed Nekron's power, enabling him to return to Earth.
Several months later, the Amulet of Anubis exploded which led to the destruction of the Tower of Fate's physical form in Salem, Massachusetts. This led to the creation of a spatial rift that formed a mystical bridge from other planes to converge onto Earth. Nekron was one of many beings that sought to exploit this opening to Earth but to do this he had to battle the demonic god known as Nebiros, who sought to rule the mortal plane. When Nekron managed to win the battle against Nebiros the souls of the undead started to pour through the rift.
However, Sentinel (Alan Scott) and Fate (Jared Stevens) appeared to confront the Lord of the Unliving before he could gain entry through the rift. With Fate's aid, Alan Scott managed to combine Fate's supernatural strength with the power of the Starheart to close the rift and once again deny Nekron's entry into the realm of the living.
Sometime later, after the Guardians of the Universe and the Green Lantern Corps had been destroyed by Parallax (Hal Jordan), the appearance of resurrected beings such as Superman had created a new anomaly through which Nekron was once again able to see into the land of the living. Seeking to expand the rift, Nekron took control of the masses of recently dead Green Lanterns and turned them against the last remaining Green Lantern, Kyle Rayner. Resurrecting Kilowog, Tomar-Re, Tomar-Tu, Adara, Chaselon, Nekron sent them after Rayner under the mistaken belief that the Lantern was responsible for the downfall of the Green Lantern Corps.
Fending off these attacks, Kyle journeyed into the Realm of the Dead and successfully closed the rift once again.
Later still, at a concert in Boston, Massachusetts, the neophyte sorceress and celebrity known as Witchfire made use of a powerful spell which unwittingly summoned Nekron to Earth. However, with the aid of Wonder Woman, Witchfire was able to help push Nekron back into the Realm of the Dead and close the rift she had mistakenly opened.
- Nekron is the final boss in the Blackest Night 8 player operation.
- Nekron first appeared in Tales of the Green Lantern Corps #2 (June 1981).
- For all his power, Nekron holds one great weakness: he cannot exist in this universe on his own power. In order to properly interact with the living world, Nekron requires a link between between the Land of the Living and the Land of the Unliving, such as a tear in space-time, or a mortal link such as Black Hand.
- Since Nekron receives power from the souls who inhabit his realm, he is constantly trying to obtain more.