She is a tough nut to crack. Introduced in Astonishing X-Men (Vol. 3) #4 (2004) by Joss Whedon and John Cassaday, Hisako Ichiki joined the Xavier Institute when it opened its door to all mutants. During the training squad exercise began, in which students were divided into groups and given codenames, Hisako was placed with Blindfold and Wing as Kitty Pryde’s Paladin Squad. She became best friends with Wing, but he was depowered during a scuffle with Ord. He became depressed and committed suicide. This caused Danger to become sentient, trapping Armor and the rest of the student body in an out-of-control Danger room. She would later protect Blindfold and Wolverine from a rampaging Beast when Cassandra Nova manipulated them. She was inducted into the X-men by Wolverine when SWORD kidnapped the team to stop Ord from destroying Earth.

After M-Day, Emma Frost set up a battle royal for the remaining students, which Armor was one of the winners joining the New X-men. She would help in the fight against the Purifiers and later Predator X. She would later join the rest of the X-men in San Fransico and later Utopia. While there she confronted Danger about her role in Wing’s death. After realizing that Danger was tormented by his death as she would see him in her memories every day, Armor agreed to teach Danger about mutants. She would later learn about her mother and brother’s death and would reunite with her father, who gave his approval for her being a member of the X-men after witnessing her fight against Fin Fang Foom.

She would later join Wolverine’s school after he fought with Cyclops during Schism. She would later feel Wolverine’s death and was distraught over his death. After the world was restore following Age of X, she would help terraform Mars by planting a Krakoa flower on the surface. She would later join the Krakoa team of New Mutants in search of Beak and his wife Angel. She was later one of the X-men summoned to Otherworld as part of the Contest of the Sword. She later joined SWORD as Ambassador-in-Training, serving under Frenzy. She would later put her name forward for nomination for the core X-men team. She didn’t success but when to space to aid Xavier and Lilandra’s daughter. After a second failed attempt in the elections, she joined Bishop’s War College.