Axiom is the ultimate weapon of the Dire Wraiths. Based on a suit of powered armor created by DeepWave Technologies, the company's Australian co-founder Aaron Grundy has been bonded with the suit in a perverse combination of Wraith magic, human ingeniuity, micromeld technology, and the mineral Ore-13. Powerful, capricious, sadistic and completely loyal to his Wraith masters, Axiom is able to evade detection from the Space Knights' Analyzers while exploiting Rom's desire to save humans who have been infected by the Wraiths.
While growing up in Adelaide, Australia, Aaron Grundy was fascinated with computers and technology. His computer interest led him to read all he could about programming, eventually landing a job at defense contractor Raymond-Lull. Grundy’s work for Raymond-Lull eventually brought him to Seattle, Washington, where, at a tech conference, he met Caleb Awan. The two men quickly became friends, and began developing what would be their ultimate achievement: the Axiom suit. After several unsuccessful attempts, the two finally began to break ground, and Grundy left Raymond-Lull to begin his own start-up with Awan, DeepWave Technologies. However, the Axiom suit's mental interface soon ran into more problems, and the two faced either losing their company, and the suit along with it, or selling it to a military think tank, ultimately opting for the latter.
After selling the company, Aaron was nervous about what the military would think when they revealed the Axiom suit's final version had been unsuccessful. However, General Joe Colton, who was sent to oversee the suit's development, presented the duo with what he believed would help the suit reach its full potential: Ore-13. Colton told them that Axiom was needed to deal with the Transformer situation brewing in Utah. After a week of development, the armor was fully operational. While Aaron told Colton that it would still take a few months to adapt the suit to anyone else's brain patterns, the General decided it was time for a field test, having two of his associates attack Grundy with "prototype" weapons. The Axiom-clad Grundy easily avoided the attacks and relieved the soldiers of their weapons. Colton concluded the suit was working perfectly. Now it was time to "work on" Aaron, knocking him out. When Aaron awoke, he found himself tied up in "bio-webs", still wearing the Axiom armor, and surrounded by Caleb, Colton, and Colton's associates, who revealed themselves to all be Dire Wraiths in disguise. The Wraiths then began to infect Aaron, merging him with the armor and transforming him into a monstrous creature.
Grundy, now calling himself Axiom, was deployed to attack the Space Knight Rom, who was traveling to Seattle with Camilla Byers. When Rom's Analyzer detected trace amounts of human DNA in Axiom, the Space Knight tried to offer his help. However, Axiom rejected it, thanking the Dire Wraiths for what they had done and reveling in his new form's power. While Rom tried to avoid fighting Axiom to uphold his vow to not harm a human, Axiom goaded him to either fight or die! Relenting, Rom readied his Neutralizer. However, before Rom could finish him off, Axiom was ordered by the Wraiths to return to base, teleporting him back when he refused.
Axiom was present when the Dire Wraith leaders, including Caleb, led a group of Wraiths to attack Autobot City beside Miles Mayhem's M.A.S.K. team. When Baron Karza enerchanged with the Dire Wraiths, Axiom was also absorbed into the giant Karza-Wraith monstrosity. Following the Karza-Wraith's destruction, Axiom lurked on an Earth rooftop, watching Rom fly off to return to his own adventures.
Having survived the destruction of the Karza-Wraith hybrid, Caleb brought Axiom along with him as he went to check up on Leonard Song's project of creating a method that would allow Rom's armor to be controlled remotely. Leonard tried to explain why progress was so slow, but Caleb ordered Axiom to kill him. Before he could strike, Leonard's control devices suddenly took control of Axiom, making him stop in his tracks. Axiom was rather unamused by this.
When the Wraiths had joined forces with Baron Karza, Axiom joined the force in Gokseong to defeat the Space Knights before Rom and the Micronauts arrived. In light of the opposition, Axiom chose to flee and report back to Karza on Hashima Island. When their foes attacked Hashima, Axiom noticed the Micronauts were missing and went off to intercept them. Though initially holding the advantage, Rom enerchanged with Axiom, stealing the hybrid's size and banishing him to Microspace.
- Aaron Grundy is named after Mysterious Universe podcast hosts Ben Grundy and Aaron Wright.
- Axiom sports three very different designs over the course of his appearances. His original Ron Joseph/Jay Fotos design in ROM: Revolution depicts him with blue-grey flesh and a black visor; under Fico Ossio and Sebastian Cheng's pens in Revolution he sports brown flesh, a glowing red visor and tattered, cloak-like wings; and in Rom & The Micronauts Paolo Villanelli and Alessandra Alexakis give him a completely different design with twisted, shadowy flesh, no visible eyes or mechanical parts, and monstrous exposed gums and teeth.
- Prior to settling on his "final" design, Ron Joseph first sketch saw Axiom as a much more monstrous, "Hulk-like" creature.
- Axiom (G1) at the TFWiki