Black Doom claims to have visited Earth over 2000 years before the events of Shadow the Hedgehog, leaving behind a flying temple-like structure that would serve as one of his instruments of conquest in the future. It is unknown why Black Doom did not attempt to conquer Earth back then.
Centuries later, fifty years before Shadow the Hedgehog, Black Doom returned to Earth and forged an alliance of sorts with humanity's greatest scientist of the day, Professor Gerald Robotnik. He offered to assist the professor with his Shadow Project by offering his own DNA to produce the ultimate life-form. In exchange, this being would assist Black Doom in acquiring the seven Chaos Emeralds, gemstones containing untold power. Using Black Doom's blood, Prof. Robotnik created Shadow the Hedgehog.
However, Gerald realized the threat his new alliance presented to Earth and secretly planned to use Shadow and the newly built Eclipse Cannon to destroy the Black Comet when it made its next regular 50 year visit. However, soon after Shadow's creation, the United Federation military force G.U.N. forcibly shut down Gerald's research facility on the Space Colony ARK and attempted to destroy all evidence of Project: Shadow. Gerald's initial plan was forgotten as he sunk into grief and madness after his granddaughter, Maria Robotnik, died.
Shadow the HedgehogEdit
Fifty years following the shutdown of the ARK, Black Doom and his army returned to Earth and launched a full-scale invasion. Shadow the Hedgehog was alive and active, but had lost his memories following the events of Sonic Adventure 2 and had no knowledge of the deal between Prof. Gerald and Black Doom.
As the Black Arms descended upon the Earth, Black Doom made contact with Shadow and urged him to locate the Chaos Emeralds. Though confused, Shadow sought out the emeralds regardless, convinced that the magical gems held the key to unlocking the secrets of his forgotten past. As Shadow hunted for the Chaos Emeralds, Black Doom subtly manipulated the hedgehog into believing that no good can come from the continued existence of humanity, offering to tell him about his past, and even goes so far as to put Shadow into a recreation of what happened to him on the Space Colony ARK to better justify the evil humans are capable of.
Black Doom's plans included the taking of the ARK for his nefarious desires. Once the ARK was under his command, Black Doom took control of the Eclipse Cannon and used it to destroy one of the United Federation's major cities. He did this so that the crater may be used as the site for the Black Comet to root in with the planet. His other plans included strengthening his armies by reawakening the temples, which were actually flying fortresses, destroying the humans' databases, wiping out all the world leaders, destroying the humans military bases, and planting the Black Arms plants around the world to slowly transform the planet into a blood-ridden wasteland.
When Shadow gains all of the Chaos Emeralds, Black Doom steals them, and reveals that he needed them all to amplify his Chaos Control to full power so that he can warp the Black Comet to Earth. The comet's own velocity was not fast enough to bypass the Earth's atmosphere and so he needed the Emeralds to perform a mass Chaos Control so that he could root the comet to Earth and use it to unleash a paralyzing nerve gas on the planet's population to make them food for his Black Arms spawn, starting with Sonic, Tails, Knuckles, Amy Rose, Rouge and Dr. Eggman. Shadow's inherited genetics from Doom make him the only other creature on the planet capable of resisting the effects of the gas. Retreating to his inner sanctum at the very center of the comet, Black Doom defends himself from his advancing offspring with a perimeter of his most elite Black Arms soldiers. When Shadow reaches him, Black Doom finally reveals the truth of Shadow's parentage but is soon after interrupted by a 50 year old transmission of Gerald from the Space Colony ARK, accidentally activated by the Chaotix Detective Agency. The transmission reveals to the world Gerald's secret plan to destroy the Black Comet and gives Shadow the resolve to defeat the tyrant. Before he can attack, Black Doom teleports outside and transforms into his most powerful form - Devil Doom. Shadow uses the Chaos Emeralds Devil Doom left behind to transform into Super Shadow and give chase. The two engage in a final battle for the Earth, in the sky over the rooted Black Comet. Shadow is ultimately able to defeat Devil Doom, sending him tumbling down to the city below to his ultimate demise.
- Telepathy - As the hive-mind of the Black Arms, Black Doom can manipulate his minions' actions as he sees fit. He has also demonstrated the ability to generate psychic illusions.
- Levitation - Black Doom's primary method of mobility, seeing as he has no legs.
- Flaming Blade - A projectile blade of flame that Doom can cast when engaged in battle.
- Meteor Strike - In his boss fight, Black Doom can summon a cluster of flaming meteors to rain down on Shadow.
- Swift Strike - A boomerang-shaped energy projectile that sweeps across the floor and bounces off obstacles.
- Phase-shifting - Black Doom can make himself briefly intangible.
- Chaos Control - The power to manipulate time and space using Chaos energy; greatly amplified when used in conjunction with one or more Chaos Emeralds.
Devil DoomEditWhen battling Shadow for the last time, Black Doom transforms into this gargantuan gargoyle-like form: Devil Doom. This terrifying form has two heads (one on either side of the torso), a pair of immense bat-like wings, and a series of roots where legs should be. These roots connect with what appears to be a boulder. He also has no eyes of his own, relying on Doom's Eye to see.
Devil Doom has a large variety of abilities. As well as retaining his flight, telepathy and Chaos Control powers, he is virtually invulnerable and can attack by breathing immense jets of fire from his mouths, mentally manipulating rocks and debris and casting energy beams. His only weakness in this form is Doom's Eye which Super Shadow is able to damage using his Chaos Spear attacks. After causing enough damage to the eye, Shadow finally slays Devil Doom and uses his own Chaos Control to warp the Black Arms off of Earth's surface, then proceeds to destroy the Black Comet with the Eclipse Cannon.
Black Doom is presented as a highly ruthless, sadistic, and power-hungry tyrant. He regards humans as pathetic creatures that have led to the destruction of their own planet. Black Doom has absolutely no affection or sympathy for anybody or anything, including his own army and his son Shadow. He gladly took the lives of his own army in order to destroy Central City, the city he choose for the site of the Black Comet when it was teleported down via Chaos Control. Black Doom has a dark lord persona in which he committed horrible atrocities throughout the story, such as attacking six cities and murdering millions, blowing up Central City, and torturing the humans and having his army eat them. He also does not tolerate any kind of mistake or failure, no matter how difficult the task on Shadow's part may be.
Black Doom's plans for the planet Earth extend much further than simply controlling the planet. His main goal is to take control of the planet and then have him and his armies feed off the humans so that his army will be invincible. According to Doom, once the planet is under his control, the humans will never see the sun again and the planet will cease to be blue. It seems Doom wants to conquer the planet as a step closer to conquering the entire universe. He sees the humans as fools who have committed crimes against themselves, and believes that he is actually trying to save them. His interpretation of saving them, however, is using them as a food supply. He believes that is their only purpose now and enabling them to become that is the same as saving them.
While Doom claims that he has Shadow's best interest, he really does not care for him and cares only for his usefulness. He often tried to manipulate Shadow's emotions in order to turn him against humanity, but this caused Shadow to see Black Doom as his ultimate enemy in the end. Doom sees Shadow as his gateway to the emeralds and his unusual skills would make him a great addition to the army. Doom often used Shadow to do tasks that would give him an advantage, such as destroying the United Federation database so information could no longer be transferred among the humans, awaking the temples to be used as weapons, and even attempting to assassinate the president.
Unlike other Sonic villains, Black Doom lacks a dry sense of humour or any humour at all it seems. He claims that he not only rules the universe, but that he is the strongest being in the universe as well (to the point of saying he is immortal), proving himself to be quite arrogant. Despite all this power he is still defeated by Super Shadow, which ironically was his fault, as he left the Chaos Emeralds with Shadow when he warped away to transform to Devil Doom, believing their power was useless against him. He reconsiders this belief during the final battle, admitting he'd underestimated the Emeralds' powers.