Created by Mark Gruenwald and Paul Neary, the character made his first appearance in Captain America #308 (August 1985).

[4][5] The Armadillo's original motivation during his criminal career was to get enough money to be able to pay a doctor to discover a way to cure his girlfriend Maria of an unspecified terminal illness.

Since that time, his motive has been to secure enough money to pay the Power Broker or some other scientist to reverse the process which transformed him.

As part of the Armadillo's first encounter with superheroes, he was dispatched by Dr. Karl Malus to break into the West Coast Avengers Compound and free Goliath.

[14] Having fallen on hard times, Armadillo proceeded to join the Constrictor and Jack O'Lantern in robbing an armored car.

[15] During the break-out initiated by Electro, Armadillo and Tiger Shark escaped and hid out in the town of Fairbury, Illinois.

[16] Afterwards, Armadillo joined Vil-Anon, a twelve-step group dedicated to helping individuals overcome their criminal tendencies.

[17] During the Civil War storyline, the Hood hires Armadillo as part of his criminal organization to take advantage of the split in the superhero community caused by the Superhuman Registration Act,[18] and he is later seen among his gang.

"[21] Around this time, he was seen entering the office of The Consultant, a criminal PR agent of sorts who improves the reputation and occasionally powers of super-villains.

[38] Armadillo later joins HYDRA after Baron Helmut Zemo promises to cure his condition in exchange for his allegiance.

He aids the Sons of the Serpent in a trafficking plot to ship illegal immigrants for a genetic experiment conducted by Karl Malus and fights Sam Wilson, who had followed the leader of the smugglers to a diner.

[42] During the "Opening Salvo" part of the 2017 "Secret Empire" storyline, Armadillo is recruited by Baron Helmut Zemo to join the Army of Evil.

[43] During the "Search for Tony Stark" arc, Armadillo rejoined Hood's gang and assisted in the attack on Castle Doom.

[51] As members of the Menagerie, Armadillo and Man-Bull fought Spider-Man and She-Hulk until Mary Jane Watson arrived in her Jackpot outfit.

[52] Due to a genetic altering procedure performed on him by the villainous Dr. Karl Malus, Armadillo has superhuman strength, stamina, and durability.

It was originally believed that his costume, a scaly nine-foot-tall orange armored hide with claws useful for digging through earth, was bonded to his skin by this process.