Mecha Superman is the result of the fusion of an Earth agro-industrial mechanoid with a damaged Kryptonian probe. The crashed probe was discovered by a young Clark Kent, who connected it to the farm's Agrobot to try to download its data. The probe quickly reconfigured the bot into a humanoid shape, and explained its origin and purpose to the amazed Clark. He dubbed the bot 'KAL', for Kryptonian Artificial Life-form, and hid it from his parents. Eventually, they discovered KAL's existence, but seeing that the bot only wished to continue its mission of exploration, agreed to keep it hidden.

Clark took it upon himself to teach KAL what it meant to be human. One of Clark's favorite methods was through playing the 'Superman' game. Superman was an imaginary, nearly invulnerable hero created by Clark. In the game, Clark - as Superman - would always save the day, righting wrongs and saving innocents from the evil 'Metallo,' an imaginary villain always played by KAL. However, no matter how many times they played the game, KAL never quite understood its point.

One tragic day, returning home from school, Clark was killed at the hands of a drunk driver. Initially, KAL couldn't process the idea that Clark was gone forever. However, as it saw Clark's parents struggle with their grief, KAL finally understood the simple and terrible truth behind Clark's game: bad things happen, and the world needs a Superman to protect it.

Although his hulking robotic form would indicate otherwise, Mecha Superman possesses a curious and trusting nature His remarkable intellect allows him to adapt quickly to any situation, although at times his natural curiosity may distract him from the matter at hand.