Armadillomon is a small armored armadillo- like digimon with three-clawed limbs and a short tail. He speaks with a Southern United States accent. Armadillomon's easy going nature is a sharp contrast to his partner Cody's serious personality.
Armadillomon is one of the three Digimon of ancient times who were sealed away by the Digimon Sovereign Azulongmon in case of a crisis. He was awakened when the Digimon Emperor began his conquest of the Digital World. Cody, on his first visit to the Digital World, lifted the Digi-Egg of Knowledge. This freed Armadillomon from his suspended animation.
Armadillomon first Armor Digivolved to Digmon on the day of his revival, when the Digimon Emperor abducted Davis. Cody's desire to understand life's mysteries evoked the power of the Digi-Egg, allowing Armadillomon to Armor Digivolve to Digmon and destroy the Dark Ring on Drimogemon, a Digimon who was under the Emperor's control.
Armadillomon later became Submarimon on the day the Digi-Egg of Reliability was found. The DigiDestined children had been trapped in an offshore oil platform by a MegaSeadramon who was under the control of the Digimon Emperor. Cody was able to invoke the power of the Digi-Egg of Reliability, allowing Armadillomon to Armor Digivolve to Submarimon. With the help of Ikkakumon, Submarimon destroyed the Dark Spiral on MegaSeadramon and freed the DigiDestined. Submarimon is one of the few digimon forms belonging to the Digimon who is well-equipped for combat in water, even able to attack Ultimates head-on. Submarimon's head also contains a cockpit that can fit a single human, meaning he can be used as underwater transport or to help destroy The Control Spires.
After Ken was no longer the Digimon Emperor and the Control Spires were slowly being destroyed, Armadillomon gained the ability to digivolve to Ankylomon. The first time was to protect Cody from Thundermon, who the DigiDestined encountered when they were helping to rebuild the Digital World after all the damage done by the Digimon Emperor.
His ultimate form, Shakkoumon was first formed when the DigiDestined were about to battle BlackWarGreymon in an effort to protect the very last Destiny Stone. Both Cody Hida and T.K. Takaishi knew they could not let the artificial Digimon destroy everyone, despite BlackWarGreymon's reasons. Their Digimon partners, Angemon and Ankylomon were able to DNA digivolve at that point, forming Shakkoumon, who teamed up with Paildramon and Silphymon to fight BlackWarGreymon.
In Dimensions, Book Four, Armadillomon finally gained access to his mega form by Biomerging with Cody to form TigerVespamon. Over the years, he and Cody have proven to be capable members of the tamers, regardless of the boy's youth in comparison to the others.
- Diamond Shell (Rolling Stone): Armadillomon curls up into a ball and rams into the opponent.
- Scratch Beat: Rapidly slashes enemies using his claws.