The Children of the Vault first appear in the X-Men arc "Supernovas," as super-powered beings who aim to exterminate both mutants and baseline humans, in order to claim Earth for themselves.

While pursuing Sabretooth, two of the Children, Sangre and Serafina, use a "singularity generator" to destroy a town in Nogales, Mexico, framing the X-Men for the disaster.

After sending an enhanced Northstar and Aurora to kill Sabretooth and the X-Men, Serafina watches from a distance with another one of the Children, Perro.

They are neither humans nor mutants, but a new species, evolutionarily distinct from either branch, created by a scientist and then cycled through normal evolutionary processes over the course of 6,000 years inside a time-accelerated cargo ship off the coast of Peru.

Rogue and her team, now including Lady Mastermind, Sabretooth, and Omega Sentinel, track and board the Children's ship.

However, in the ensuing fight, the X-Men are overwhelmed, with Iceman essentially vaporized by Fuego, as the Conquistador hovers over the Xavier Institute, ready to destroy all the mutants within.

Many of the Children of the Vault (including Perro) manage to escape the battle alive, leaving behind animal carcasses altered to resemble them.

The survivors, led by the mysterious Cadena, are revealed to have escaped to Ecuador, to the abandoned Sentinel facility once used by Cassandra Nova.

A rebellious young member of the Children, Luz, escapes from the group's new headquarters, the futuristic city "The Corridor" (also known as Quitado), and lands in Mumbai during what appears to be a magnetic storm.

When "Luisa" demonstrates her ability to paint colors in the air via light manipulation, Rogue, suspecting her to be a mutant, offers her hospitality at Indra's family's home.

The remaining Children, led by a woman named Corregidora, pursue Luz, whom they believe to be critical to something called "Angelfire."

Angelfire, Cadena explains, is a new, cleaner engine, to be powered by "the 30," a group of Children including Luz—and the captured Magneto.

After Serafina's capture and escape from Orchis and the rise of the nation of Krakoa, the city has created the third generation of Children so they can eventually take over Earth.

Before dying, however, Synch manages to make telepathic contact with Professor Xavier and ensure everything he's learned about the Children of the Vault is passed onto his resurrected form.

Sangre drowns Thing, Fuego kills Human Torch, Mister Fantastic is dead on the ground, and Serafina snaps Invisible Woman's neck.

Insatiable, the Children of the Vault journeyed to Asgard, where they killed everyone and ate a feast on top of Thor's dead body.

Presenting themselves as the "Children of Tomorrow", they shared their technology with afflicted regions of the planet in order to gain the world's trust.

Cable used his strain of the Techno-Organic Virus to infect the Children's city, which would not only engulf them all, but also form a Spire that would summon the Technarchy and devour the entire Earth.