Imperiex is a fictional character that appears in comic books published by DC Comics. The character first appears in Superman (vol. 2) #153 (February 2000), and was created by Jeph Loeb and Ian Churchill. He was the main villain for the "Our Worlds at War" crossover.
The embodiment of entropy, Imperiex takes the form of pure energy contained inside a humanoid set of armor, colossal in size. Since the dawn of time, he has repeatedly destroyed the universe to create a new one from the ashes of the old. He is first mentioned when Mongul, the son of the deceased villain of the same name, arrives on Earth stating that Imperiex has destroyed his Warworld and is heading for Earth. Mongul convinces Superman to help him fight Imperiex, and the two apparently manage to defeat it. However, it transpires that the "Imperiex" they encountered was no more than a probe, whereas Imperiex Prime, leader of the Imperiex probes, is himself a much larger and more powerful being. He has detected imperfections in the fabric of the universe, and his ultimate plan is to destroy it and create a new, perfect one. To do so, Imperiex Prime heads for Earth- the planet which holds the universe together after being the center of the Crisis on Infinite Earths, in order to destroy it and thereby induce a new Big Bang.
Before arriving on Earth, Imperiex obliterates countless other planets including Kalanor, Karna, and Daxam. Whole galaxies are also targeted for demolition. After destroying Karna, Imperiex arrives at Almerac, the home of Maxima, and not only destroys Almerac but "hollows" the whole galaxy. After this, the survivors of the dead worlds, along with Earth, Apokolips and Brainiac 13's new Warworld, form a coalition, with Darkseid as its commander, to fight against Imperiex Prime and his probes, which are created by Imperiex's ship. Finally arriving at the Milky Way Galaxy, Imperiex sends in numerous probes, which are revealed to be machine-colony "Hollowers". On Earth, these machines destroy Topeka, Kansas, seven other places on Earth's seven continents and Atlantis, when they began to dig into Earth to ready it for Imperiex's final demolition.
President Lex Luthor rallies the super-heroes of Earth, the U.S. military, and other countries, such as Pokolistan, together. Luthor decides that Superman alone does not have enough power to lead a strike force, and instead arranges for Doomsday to be released from captivity, 'anti-hero' telepath Manchester Black temporarily 'reprogramming' Doomsday's mind so that his traditional hatred for Superman is briefly transferred to the Imperiex probes. Superman and Doomsday fight the probes and manage to destroy several until Imperiex Prime himself is finally drawn to them. Doomsday is outmatched and vaporized, only his skeleton remaining, though Darkseid saves Superman from a similar fate. Thanks to the sacrifice of Strange Visitor and General Rock, Earth's forces managed to crack Imperiex's armor, intending for Darkseid to use Boom tubes to transfer Imperiex's energy back to the galaxies he'd destroyed to prevent them from triggering a new big bang. However, Brainiac-13 appears on the battleground with Warworld, absorbing the Imperiex energies and vowing to use them to rule everything. Superman dives into the sun to acquire a sufficient power boost to oppose Brainiac, but when it is discovered that Warworld cannot be destroyed without releasing Imperiex and triggering another Big Bang, he has the Martian Manhunter form a telepathic link with other combatants to make a last-minute plan.
With his powers weakened following Brainiac's attack Darkseid uses Tempest as a magical focus for his abilities, empowered by the faith and strength of the Amazons, and focusing his energy through Steel's new 'Entropy Aegis' armor (created on Apokolips from a burned-out Imperiex probe). Meanwhile Lex Luthor activates a temporal displacement weapon on Earth. The weapon's energies are then combined with Darkseid's Apokolips energy to create a temporal boom tube. Using his new power boost, Superman is able to literally push Warworld itself through the boom tube, sending both Imperiex Prime's and Brainiac's consciousnesses back to the Big Bang, destroying both villains through a combined effort while negating any effect they would have had on the present. In his final moments, Imperiex Prime realizes, in an ironic twist, that the imperfection he had detected in the universe was himself.
At least 8 million people on Earth die during the war. The total number dead in the DC Universe is stated to be countless. Several heroes also die including Maxima. Aquaman, Doomsday, Guy Gardner, Queen Hippolyta, General Sam Lane (Lois Lane's father), and Steel are all presumed dead, but later return alive for different reasons.
Imperiex appears in the Legion of Super Heroes animated series, voiced by Phil Morris. The character was deemed to be a big enough threat to be used as the primary villain for the entire second season, but enough of a blank slate that his "real" DC Universe history could be modified for the TV version. As opposed to his comic-book incarnation, this Imperiex relies on physical, direct combat. He can fly, is stronger than Superman and is, for the most part, virtually indestructible. The only time he is vulnerable to few, if any kind of head-on attack is when he uses a cannon mounted in his chest, which is also his most powerful weapon, but even using that very weakness against him only succeeds in defeating him for a few minutes. In addition, he has extendable claws and he wields a pair of powerful swords that can fire out waves of energy. He can also create and control armies of Destructo-Bots and is exceptionally intelligent and cunning, evident by the fact that some of his Destructo-Bots are shown to know how to take their enemies down with them. In the show, Imperiex was originally an alien (presumably from the planet Apokolips) who was raised in a gladiator lifestyle; over time he had his body modified by technology that was created by a scientist named Abel, that allowed a perfect union of organic tissue with cybernetics, until nothing remained of his original self. In the 41st century, Imperiex had conquered most of the universe and wiped out nearly all resistance that stands in his way, with a clone of Superman named Kell-El among the forces left to oppose him. Unable to stop Imperiex and his army, Kell-El travels back to the 31st century to recruit the Legion of Superheroes to help stop Imperiex. Although Brainiac 5 comes up with a plan that appears to stop him by taking advantage of his weak point, Imperiex is able to take the device Kell-El used to travel through time and use it to escape to the Legion's timeline. After escaping to the 31st century, Imperiex secretly frees the Fatal Five and the Legion of Super-Villains from prison, recruiting Validus. He hacks into Computo, downloading information about the Legion's arsenal at the time as well as acquiring some data that he offers to the Dominion. Outside of Validus, the Dominion, and his Destructo-Bots, Imperiex works with and recruits villains such as Mekt Ranzz, Ron-Karr, and Grimbor the Chainsman to aid him, although he was perplexed by those villains when they left him. In "Unnatural Alliances," the cybernetic villain Terra-Man targets a younger Abel which Imperiex couldn't allow. In the final fight with Terra Man, Superman X and Imperiex agree to work together to destroy Terra Man. In "Message in a Bottle," Imperiex and his armies invaded the Fortress of Solitude so he could steal "The Messenger" from the shrunken city of Kandor. Brainiac 5 was forced to tap into his ancestor's knowledge and use it to turn the sun yellow, allowing the Kandorians to fight back and cause Imperiex's army to retreat. However, it turned out that Imperiex intended for Brainiac 5 to do that in order for him to succumb to the original Brainiac's influence and become an ideal member of his campaign. When this plan succeeded, he did a transmission to the Legion of Super Heroes stating that Braniac 5 has joined up with him. During the transmission, Imperiex ultimately ends up being impaled by Brainiac 1.0 (in Brainiac 5's body) who thanked him for his part of bringing him back, but coldly stated he was no longer of any further use to him. He then kills Imperiex in a violent unseen way, robbing Kell-El the chance of killing the tyrant himself.