Unicron

Unicron is a fictional character and supervillain from the Transformers media franchise. Designed by Floro Dery, he was introduced in the 1986 animated film The Transformers: The Movie and has since reappeared in Transformers: Armada, Transformers: Energon, Transformers: Cybertron, Transformers: Prime, Transformers: The Last Knight and Atari's 2004 Transformers video game. Unicron is a prodigiously large robot whose scale reaches planetary proportions, and he is also able to transform into a giant planet. Unicron's origin has expanded over the years from simply being a large robot to being a god of chaos who devours realities. He often employs the help of Decepticons in his work, and in some stories is considered part of the origin of the Decepticon forces.

The Transformers: The Movie
In the year 2005, Unicron made his most famous attack upon Cybertron. While heading towards the planet, he consumed the small world of Lithone, making it perfectly clear how great of a threat he was to the entire universe. As he continued on his way, Unicron's powers allowed him to become aware of the death of Optimus Prime, who handed the Matrix of Leadership to Ultra Magnus just before dying, which angered him tremendously. He then came upon the bodies of several wounded and dying Decepticons, who had been dumped into space following a recent battle on Earth. He extended a proposition to the Decepticons' leader, Megatron, offering to rebuild his body and those of his troops in exchange for their destruction of the Autobot Matrix of Leadership. Tortured into accepting, Megatron was transformed into Galvatron, and his followers became Cyclonus, Scourge, and the Sweeps.

While Galvatron set about reclaiming leadership of the Decepticons, Unicron arrived at Cybertron, and proceeded to consume the planet's two moons. Outraged that Unicron would do this to a planet that he viewed as his, Galvatron found himself the victim of mental torture by his creator, and ordered to Earth to complete the task given him. The ensuing chase finally climaxed in a showdown on the planet of Junk, where Galvatron seized the Matrix and returned to Unicron, only to reveal that he intended to use the talisman to make Unicron his slave. Amused by his pawn's arrogance, Unicron transformed into his gigantic robot mode and ate Galvatron. Unicron then tore into Cybertron, as Shockwave and the rest of the Decepticons on the planet fought back, to little effect. Unicron swallowed many spaceships, and one, which contained the young Autobot Hot Rod and his comrades, crashed through Unicron's eye. Hot Rod and Galvatron battled deep inside Unicron, and ultimately, Hot Rod was able to retake the Matrix from the Decepticon. Transformed by its power into Rodimus Prime, he defeated Galvatron and opened the Matrix inside Unicron, destroying his body from within.

Unicron's head was blown clear during his death throes, and became caught in Cybertron's gravity, turning it into a new moon for the planet — a grisly testament to the satellites he had destroyed.

Transformers Beast Wars
When Starscream appeared on prehistoric Earth and was questioned by the stranded Predacons about how he came to be this way, Starscream "explained" that his body was destroyed by Unicron while serving his master, Galvatron. This was, of course, a misrepresentation, and it was revealed later that it was actually Galvatron himself who killed Starscream. When the Vok spoke with Optimus Primal in Earth's pre-history, they took the form of Unicron's head, claiming that they scanned his mind and chose Unicron as an "authority figure". Megatron would later invoke the name of Unicron by referring to Tarantulas as "Unicron's spawn" in a derogatory manner.

Transformers Unicron Trilogy
In Armada, Unicron's first attack on Cybertron in the present day was an indirect one, over a million years in the making, begun when he opted to disguise his dormant body as Cybertron's moon. From this secret vantage point, he implanted his own cells within the planet, where they germinated and grew into the small race of robots known as the Mini-Cons. Unicron hoped to use the Mini-Cons to increase the ferocity of the Autobot/Decepticon war, and feed off of the energies released in the conflict, but an encounter with a group of time-displaced human children planted the seed of sentience and free will within the Mini-Cons, who ultimately rebelled against their creator and fled Cybertron, crash-landing on the planet Earth.

When the Mini-Cons were reawakened a million years later in 2010, they were detected by the Autobots and Decepticons, who followed their signal to Earth. Unicron also picked up the signal, and dispatched his minion Sideways, an inhabitant of Planet X who would occasionally serve as an avatar for Unicron's spark, to carry on his work. Sideways escalated the conflict by manipulating control of the three Mini-Con weapons, the Star Saber, the Skyboom shield and the Requiem Blaster, but eventually arranged for all three to be returned to Cybertron, where he stole them and used them to reawaken Unicron.

Shedding his moon disguise and transforming to robot mode, Unicron turned on Cybertron, only to be met with resistance in the form of the united armada of Autobots and Decepticons, and his own Mini-Cons, who had linked together and formed a giant duplicate of his body. Now at full power, however, it was child's play for Unicron to exert control over his creations, and bring the Mini-Cons under his thumb once more. Again, it was thanks to the Autobots' human allies—the same children who had been sent back in time and given the Mini-Cons free will in the first place—that the Mini-Cons struggled free of Unicron's control, including the three Mini-Con weapons, who broke free and left Unicron's body deactivated. Believing the threat over, Galvatron then challenged Optimus Prime to their final battle, only for the hatred and ferocity of their fight to awaken Unicron once more. To end the circle of hate that gave Unicron life, Galvatron allowed himself to be consumed by the monster, and in a brilliant flash of light, Unicron apparently ceased to exist.

In Energon, Unicron had survived, and for the next ten years, continued to consume planets in other regions of space. One such planet was the world known as Planet Q, whose inhabitants fought back by detonating the planet's core in Unicron's face. Badly damaged by the explosion, Unicron fell into a state of dormancy, but the life essence of the planet's ruler—the being who would come to be known as Alpha Q—continued to exist within him, and began a not-entirely-sane plan to use Unicron's powers to recreate everything the Chaos-Bringer had ever destroyed. Alpha Q: Identity Recreating the armies of Planet Q as "Terrorcons", Alpha Q had them attack Autobot facilities on Earth and throughout the solar system to gather the energon that would be necessary for his plan to work.

Unbeknownst to Alpha Q, Megatron's corpse and spark remained within Unicron, and he slowly siphoned off some of the gathered Energon, allowing him to be reborn in his own new body. To escape Megatron's fury, Alpha Q jettisoned Unicron's head and escaped in it, while Megatron took over Unicron's body, and continued to gather Energon in order to rebuild Unicron to use as his ultimate weapon. As the climax of this plan neared, a joint attack by Alpha Q, the Autobots and their human allies saw all of Earth's Energon channeled into Unicron's head, which Alpha Q then rammed into Unicron's body. The positively-charged Energon of Earth reacted with the negatively-charged Energon running through Unicron, tearing open a fissure in reality leading to a new area of space where planets Unicron consumed were recreated, and sustained through the Energon radiated from Unicron's head, which had now become a glowing red sun.

Unicron's body, damaged once more, lay in the dark reaches near the fissure, and the Decepticons began to raid Alpha Q's new planets for the Energon necessary to revive Unicron again. A Heroic Battle This time, they succeeded, and Megatron directed Unicron's body to retrieve his head, extinguishing the Energon Sun and killing Alpha Q in the process. But the power of Unicron proved too much for Megatron to control, as Unicron began to take over Megatron's body. The Autobots made a valiant but futile attempt to stop him, but Unicron decimated them. Just as things seemed hopeless, a surge of power came that allowed Optimus-Supreme to grow to Unicron's size and powered up the other Autobots, and after a long and hard battle Optimus destroyed Unicron's body.

Transformers: Universe
According to legend, at the beginning of time, Unicron and Primus battled each other for eons, with neither side remaining victorious for long. Until, that is, Primus created the Thirteen. These Thirteen defeated Unicron and cast him into space.

Unicron was a being older than recorded history and a devourer of worlds, and was a myth to Cybertronians, much to his content. The ancient genius known as Primacron found Unicron's fallen form and used the god's CNA to construct his creation and named it after the dark god. Primacron had hoped that the prototype Unicron would scour the galaxy clean of life, leaving a blank slate for him to experiment upon, but naturally, the prototype Unicron had no desire to be the servant of another, and turned on Primacron, badly wounding him and his assistant, and setting out into the depths of space.

Unicron's first attack on Cybertron was over a million years in the making, begun when he opted to disguise his dormant body as the Nameless Planet. From this secret vantage point, he implanted his own cells within the planet, where they infused into the birthing chamber at the center of Cybertron. Primus created the small race of robots known as the Mini-Cons to help the Transformers. Unicron hoped to use the Mini-Cons to increase the ferocity of the Autobot/Decepticon war, and feed off of the energies released in the conflict. The Cybertronians would then be subjugated through the Mini-Cons' influence. Though his plan succeeded in one timeline, the interference of three time-displaced children changed this. With help of Rad White, Carlos Lopez, and Alexis Thi Dang, Primus planted the seed of sentience and free will within the Mini-Cons, who ultimately rebelled against the dark god and fled Cybertron, crash-landing on the planet Earth. This forestalled Unicron's emergence by eons.

As the prototype Unicron slept, the Mission of Cybertronian Expansion ship, the Proudstar touched down on his surface. He observed the crew members and eventually corrupted them to varying degrees, particularly their leader, Nova Prime. His influence caused them to begin cyberforming inhabited worlds as well as uninhabited ones, wiping out millions of lives. Before the Proudstar left, Nova pointed Unicron in Cybertron's (and Primus's) direction. The more distance the crew put between themselves and Primus, the more Unicron managed to corrupt them. Kranix and Jhiaxus separately realized what Unicron had done to them but could not stop it. Kranix eventually caused the ship to crash into Earth before he fled to Lithone. Unicron, meanwhile, followed the trail of cyberformed worlds, destroying all he came across in the process. Millions of years later, a touch of his darkness still permeated in the Proudstar. Optimus Prime felt him through the Matrix. Teletraan Alpha seemed to know that Unicron represented chaos but not who he was. The supercomputer predicted Unicron's eventual defeat to Optimus Prime and his Autobots.

Fanon/Idea Wiki Appearances

 * Unicron appears in the Disney+ crossover miniseries Marvel's All-Star Multiverse, voiced by Bob Joles. In the past, he attempted to destroy Earth and Cybertron until he was defeated by a brief alliance between Autobots and Decepticons, with Optimus Prime destroying him after a scuffle with Megatron (as Galvatron). In present day, Unicron appears a spirit summoned by Thane along with the spirits of other universes' dark lords (consisting of Knull, Emperor Palpatine, Mephiles the Dark, and Za-Naron). He and the dark lords entrust Thane with the task to destroy the "light of the Multiverse".
 * Unicron appears in the Paramount+ animated series Transformers: 'Til All Are One, voiced by David Kaye. He serves as the main antagonist in the second season.