He was first seen in armored humanoid form on the Red Planet to assist in its mechanization, where he was fought to a standstill by Soldato J (002). This duel left an unresolved grudge between the two of them, one that would be suspended after J was mechanized into the Zonderian Pizza and his memory of the conflict suppressed. Arm would later face Soldato J again, in a different time and place—the GGG Orbit Base, during his assault on it as leader of the Magnificent 7 Primevals. (To assist him with this task, he also fused with the US battleship USS New Jersey as needs warranted.) As a last stand in that encounter, he would escape to Earth's Moon and perform Primeval Fusion with five of the remaining six Primevals in his group; this gambit would fail, although he managed to secure his own