Not much is known about the being known as Annihilation, apart from the fact that it is a dark god from the hellish dimension of Amenth and the ruler of its Daemons. There are many myths about it including that it is an elder god, a primordial force or the spirit of Amenth made manifest. At some point in time, Annihilation gave birth to the demons, and allowed them to feed on its body, until only its spirit remained, trapped in the Golden Helm. 
Wars Against the Mutants
Thousands of years ago, its army broke free from the dimension of Amenth and emerged on Okkara, where its Daemons battled Okkara's mutant population, led by Apocalypse, his wife Genesis, and their Four Horsemen. At one point during the war, the mutants gained the upper hand, prompting Annihilation to offer peace terms spoken only to Genesis. The terms were rejected, but eventually it became clear that the mutants could not win. In an effort to buy time, the mutants sealed the breach through which Annihilation and its armies had emerged. Okkara was permanently split, with one half (Arakko) being sealed within Amenth, and the other (Krakoa) remaining on Earth. Genesis, the Horsemen and the rest of the mutants remained on Arakko to continue the battle against Annihilation, in an effort to buy time for Apocalypse to find the means of defeating Annihilation once and for all.
As the years went on, Arakko remained a bastion for the Okkaran mutants, while Annihilation kept sending its forces to attack them, capturing the Okkaran mutants who had been lost in Amenth and breeding them with daemons in order to produce powerful hybrids. After Genesis' failed in her attempt to break the demonic armies once and for all, Annihilation challenged her to a fight to the death to settle who would rule Amenth. Genesis won the duel, only to realize that it had been a trap; without a host, the horde of daemons would run rampant and destroy Arakko. This forced Genesis to don the golden mask of Annihilation, merging the two, and giving Annihilation control over Arakko and its mutants.
X of Swords
With Arakko finally conquered, Annihilation and its new Arakkan vanguard set about conquering other realms, attacking and destroying Dryador. In an effort to once again find its way to Earth, Annihilation sent Summoner and a piece of Arakko to Earth, in order to make contact with Apocalypse and lure him into opening a gateway between Krakoa and Arakko. The plot was successful, and Annihilation's forces ambushed the Krakoans who had been lured to Amenth. However, Annihilation's conquests had attracted the attention of Saturnyne, who intervened in the conflict. She offered to arrange a contest to settle the conflict between Arakko and Krakoa. Death agreed to the terms, on behalf of Arakko.
Annihilation possessing Genesis then observed behind the scenes as the tournament proceeded. Following the battle between the White Sword and Gorgon, the scores for Arakko and Krakoa were even. The final event, which would settle the tournament, would be a duel between Apocalypse and Genesis. During their battle, Genesis, initially without the Golden Helm, seemed to have the upper hand as she managed to destroy her husband's sword, but suddenly Apocalypse grabbed her sword, the Twilight Sword, and shoved it into her stomach. She begged Apocalypse to kill her, but he refused, allowing Annihilation to take control of Genesis and summon almost all of the Amenthian forces to Otherworld, intending to conquer Krakoa for good.
However, as the battle raged on the Champions of Krakoa were joined by the reassembled X-Men and Captain Britain Corps and eventually the Vescora. As the war was seemingly turning in Krakoa's favor, Apocalypse was able to remove the Golden Helm from Genesis' head, causing it to possess Apocalypse. However, unlike Genesis, Apocalypse was able overcome Annihilation's influence and conceded the tournament on Amenth's behalf. After that, Saturnyne turned the Golden Helm into a staff, dulling Annihilation's corruptive influence, and gifted it to Genesis. She also decreed that Amenth and Krakkoa would exchange one hostage each, as a show of good faith. On behalf of Amenth, Genesis chose Apocalypse, and on behalf of Krakoa, Apocalypse chose Arakko itself, including all the mutants trapped on it.
- Possession: Bound to a helmet, Annihilation requires a host to properly interact with the outside world. It is unknown if Annihilation still possesses this ability due to Saturnyne transforming it into a staff.
- Limited Shapeshifting: Annihilation was able to somewhat change its appearance such transforming from a golden pharaoh headdress-like helm to a green tentacled parasite-like creature, and can also adapt to its wearer head and face.
- Hordes of Amenth: Annihilation was stated to have full command and control of the seemingly endless hordes of Daemons born on Amenth and can command them to do their bidding. Annihilation's hosts are also granted this ability once they put on the helmet.
- Dark Energy Manipulation: Annihilation was seen emitting dark energy in form of lighting, although it didn't use this power on its enemies.
- Sword Combat: Annihilation is seemingly skilled in sword combat.
Host Dependency: Annihilation is unable to move or feel anything without a host to wear the golden helm. Furthermore, while the host wears it, their body will rapidly decay, forcing Annihilation to seek another one.
- The Golden Helm of Amenth: Once worn by someone, the power of Annihilation takes over their body completely. However, only individuals of great strength can survive the experience as it is shown that the dark god’s power can overwhelm the wearer and disintegrate their body. It is unknown if Annihilation still possesses this ability due to Saturnyne transforming it from a helm into a staff.
- Annihilation shared many traits with SCP-035. Both being living mystical headgears needing a host to interact with the outside world, while the host's body decays and are both linked to eldritch divinity. It is unknown if the resemblance was coincidental or intentional.
- 4 appearance(s) of Annihilation (Earth-616)
- 2 minor appearance(s) of Annihilation (Earth-616)
- 31 image(s) of Annihilation (Earth-616)
- 1 item(s) used/owned by Annihilation (Earth-616)