The Children of the Vault are not mutants, but highly evolved beings who have evolved from a baseline human genetic base over a time period of 6,000 years. Their society was raised in the hold of a ship where temporal acceleration technology was used to evolve a collection of individuals into superpowered beings. Due to genetic drift, they are a separate species from either baseline humans or mutant humans.
A research group under Bella Pagan proposed a theory of temporal acceleration and parallel evolution in the early 70's. Largely derided by the scientific community, they found backing in South America, gaining a tanker from the Chilean government. Knowledge of the project was largely lost until one of the scientists, Doctor Casales, grew guilty over the group's unethical actions, and hired Sabretooth and his associate Pasco to kill those who had worked on the project. After killing Casales, Sabretooth found the location of the tanker. They reached the ship, the Conquistador, on M-Day, and Pasco lost his mutant powers. The Children emerged, having spent the equivalent of 6000 years in evolutionary and technological advancement. Pasco died in the resulting conflict, but Sabretooth escaped.
The Children of the Vault evidently believe that only one race can survive as absolute ruler of the planet, and they intend to be that species. They sought to eliminate Sabretooth to keep their existence secret until they were ready to strike out at the large world. In their attempts, they casually destroyed a town in Nogales, Mexico, and manipulated survivors and the media into thinking that the X-Men were involved. The X-Men located Sabretooth while investigating the allegations. While the Children had intended to draw Sabretooth out and kill him, they had not planned on revealing their existence to any more people. To kill the X-Men before they could learn of the Vault's existence, they recruited mutants Aurora and Northstar. Killing all of the members of the S.H.I.E.L.D facility where Northstar, were the two held captive, Serafina interfaced with the simulations being used to brainwash them, and warped them to her own ends. Images of the X-Men were doctored into the security footage by Serafina, allowing for a similar attempt to discredit the team. They also enhanced the powers of the twins so that they now produce a powerful heat blast when touching.
After sending Northstar and Aurora to kill Sabretooth and the X-Men, Serafina and Perro watched from the distance. The surprise attack was initially successful, seeing the apparent death of Iceman and severe injuries to many of the X-Men. Luckily, Aurora was defeated thanks to Mystique's manipulation and Iceman's surprise (though incomplete) reformation, and Northstar was defeated by the combined efforts of Rogue and Cable.
In interrogations after the fight (which saw intense damage though supposedly only lasting five minutes), Cable learned through Sabretooth that their enemies were known as "The Children of the Vault", were neither mutant nor human, and wanted him dead simply for learning of their existence. Sabretooth took a certain amount of pleasure in this revelation, as it now put the X-Men “on the endangered species list” along with himself.
Meanwhile, Serafina used her cloaking abilities to infiltrate the mansion directly. She was invisible to telepaths, and Wolverine was only mildly aware of something amiss. Still, she easily made her way to the injured Lady Mastermind in the infirmary, and hijacked her abilities to trap Cannonball in an illusion. Cannonball identified gaps in his memory (as from his perspective he had been living a span of decades within the illusion, and confronted his mysterious new wife, Serafina. Serafina gave up on trying to manipulate Cannonball, but was interrupted before she could kill him.
Rogue's X-Men team, along with Sabretooth (controlled by micro-sentinels), and Cable, engaged the Children in battle on the Conquistador. At the same time, they decided that all secrecy have been lost, and raised the Conquistador into the air. The now-flying ship quickly made for the Xavier's School for Gifted Youngsters, where the Children intended to destroy the majority of the world's remaining mutants. Rogue's X-Men managed to defeat the children by the narrowest of margins before they could annihilate the academy.
With his last breaths, Sangre (who was mortally wounded by Mystique, who shot him with thermite bullets), tried to ram the Conquistador into the school, but it was stopped at the last minute by Cannonball and the ONE Sentinels. Many of the Children did manage to escape the brawl alive, such as Perro, leaving behind some three thousand animal carcasses changed to resemble them, so that the X-Men had believed they were destroyed in an explosion on the ship. They then escaped to Ecuador, to hole up in the abandoned Sentinel facility once used by Cassandra Nova, and are now being led by the member known as Cadena who says they will continue with their plan, and the X-Men will not see them coming.
The Children of the Vault once again came into conflict with the X-Men when one of their number, Luz, escaped their extra dimensional city, the Corridor, to avoid being conscripted into their Angelfire Project, which would used 30 people with energy-based powers to generate enough energy for their entire city forever. She escaped into Mumbai, where she used her light-based powers to create an illusion that let swap places which one of the natives. When the Children captured Luz's doppelganger and plugged her into the Angelfire machine, her lack of power caused the machine to malfunction and crashed the Corridor into Mumbai. 
Equipment: Various advanced technologies
The Children of the Vault are very similar to the Neo.
- 11 Children of the Vault (Earth-616) Members
- 10 Appearances of Children of the Vault (Earth-616)
- Minor Appearances of Children of the Vault (Earth-616)
- Media Children of the Vault (Earth-616) was Mentioned in
- 5 Images that include Children of the Vault (Earth-616)
- Team Gallery: Children of the Vault (Earth-616)