Like S.H.I.E.L.D. was established for global security and S.W.O.R.D. for extraterrestrial security, A.R.M.O.R. was established as a force of extradimensional security to guard against contamination and conflict from alternate realities. A.R.M.O.R.'s central command is known as the Hollow and is a bunker miles underground that is accessible only by teleportation. Charles Little Sky (Portal) serves as the agency's director and was chosen in part because of his ability to create interdimensional portals.
The agency monitors areas on Earth where perpendicular and wave universes naturally intersect with the 616 Earth. The largest cluster of intersecting universes is known to be in Citrusville, Florida.
While responding to a call for help, the Command, Florida's Initiative team, was ambushed by locals who had been infected with a zombie plague brought by another reality's Deadpool. The Command's leader Siege -- apparently an agent of A.R.M.O.R. -- quickly became infected. Protocols programmed into his cybernetic systems by A.R.M.O.R. terminated him and alerted the agency to the crisis.
Morbius, who had been recruited by A.R.M.O.R. as an expert on biological threats, formulated a vaccine that would inocculate against the extradimensional zombie plaque. However, he would need a blood sample from a living person on the source Earth to create it. Director Little Sky deputized Jocasta and Machine Man for the mission, since they could not be infected. What DIrector Little Sky didn't realize was that A.R.M.O.R. had been infiltrated and Morbius was actually his zombie counterpart. Rather than a vaccine, this Morbius intended to infect the entire Fifty State Initiative.
While Jocasta and Machine Man were on the other Earth, the Hollow was overrun by a zombie outbreak as the alternate Morbius made his move. Director Little Sky ordered Jocasta to secure the teleportation bays to keep the outbreak from spreading to the surface. None of the infected A.R.M.O.R. personnel could be allowed to escape. The real Morbius was freed and staked his zombie counterpart, while Machine Man's arrival helped contain the rest. The situation was brought under control.
However, it was discovered that someone had made it out of the Hollow before Jocasta secured the teleportation bay. Morbius asked Director Little Sky to be allowed to lead the unit to pursue the remaining zombies. That unit would be called the Midnight Sons.
Operation: Midnight Sons
Morbius was dispatched with Jennifer Kale, Daimon Hellstrom and Werewolf By Night to contain the zombie outbreak. The breach of Hollow security was perpetrated by the zombie Simon Garth, who was brought in to test for answers against the alternate reality zombie plague, and the head of the alternate reality Deadpool, who carried the plague.
The situation escalated when the plague came into the possession of Black Talon, who intended to sell it to the Hood. The Midnight Sons clashed with the Hood's thugs of choice, the Night Shift. Making matters even worse, Morbius' vaccine failed. The plague mutated, becoming an incredibly deadly airborne entity.
A.R.M.O.R. was prepared to unleash a nuclear strike to sterilize the whole region, but the Midnight Sons were able to combine Kale's Atlantean sorcery and Black Talon's voodoo to bottle up the airborne plague into the body of Simon Garth, who was then taken into A.R.M.O.R. custody.
DIrector Little Sky informed Morbius that he would like to keep the Midnight Sons on call. The zombie plague was not the first monster from another reality to try to get loose on their Earth, and it was unlikely to be the last.
Lyra the Savage She-Hulk
A.R.M.O.R. tracked an incursion from Earth-8009 into New York, which turned out to be Lyra the daughter of Thundra and Hulk from an alternate future reality. Intercept teams were dispatched, but she tore through them upon her arrival. She was monitored going to the ruins of Avengers Mansion, where she abducted A.R.M.O.R. agent Alexander Erde to use as a field guide for this reality.
She-Hulk was sent in to try to reign Lyra in under A.R.M.O.R.'s authority, and she nearly succeeded after Lyra was discovered to get weaker the angrier she becomes. However, Sentry interfered and pitched She-Hulk from the fight, allowing the Dark Avengers to take over. They were able to capture Lyra, and Norman Osborn hoped this incident would allow him to fold A.R.M.O.R. into the control of H.A.M.M.E.R.
With the help of She-Hulk, Director Little Sky was able to have both of the gamma women teleported directly out of Avengers Tower to the Hollow. He now realized that Lyra was not here as part of an attack and therefore not the threat he assumed her to be. However, she would still have to be deported back to her home reality. She preferred not to go back though and possessed downloaded information on Osborn's covert dealings to negotiate a deal.
This deal allowed Lyra to remain on Earth-616, as an agent of A.R.M.O.R.
A.R.M.O.R. became aware of a planestorm in the multiverse, where several realities clashed and tethered together to allow for easy crossovers between them. What was unique about this planestorm was the many of the realities involved were experiencing their own zombie plagues. Seeking to further understand and cure the zombie plague, Morbius sent newly recruited A.R.M.O.R. agent Howard the Duck and Machine Man on an unauthorized mission into the planestorm to collect samples of as many unique zombie types as possible.
On an Earth where the wild west was still the present day. the two agents deputized Swift Cloud, the daughter of Hurricane, to help them in their mission. She had little reason to stay on her own Earth considering she just witnessed zombies eating her father.