Armor's real name is Hisako Ichiki She is a teenage mutant from Japan that studied at the Xavier Institute before becoming an X-Man. Her mutant power allows her to create psionic "armor", giving her enhanced strength and durability. She is currently enrolled at the Jean Grey School for Higher Learning.

Hisako's psionic armor acts as an extension of (although can be much larger than) her own body, which enhances her strength level and resistance to injury. While using her armor, Hisako has demonstrated the ability to hurl Wolverine and even assisted Colossus in restraining a small ship capable of breaking orbit from lifting off.

Her armor is generally impervious to most damage (as long as she can maintain it), but both lasers and Wolverine's claws have been shown to be able to pierce it, but he himself is unable too. Her armor is made from psionic energy, and has said it's her "ancestors", most probably meaning that's where the psionic energy comes from. It has also been mentioned that when someone with the same powers as her along her ancestry dies, then the armor grows bigger and stronger. Hisako can also release her force field into a concussive blast of energy, but it takes lot of concentration.

Armor's real name is Hisako Ichiki. She originally came to the Xavier Institute with the hope becoming one of the X-Men. Shortly after her arrival, Armor and her trusted friend Wing are attacked in the Xavier Institute during an assault by Ord, an alien villain from Breakworld. Ord overpowers the two and injects Wing with a mutant "cure". Luckily, they both survive.

Hisako was created by Joss Whedon and John Cassaday and first appeared in Astonishing X-Men #4 in October 2004.