Rex was once a penniless street orphan selling cheap lemonade alongside a rusted scrap robot until the legendary Mech King Victor pulled him from an alien swarm and gifted him a rare energetic core. That singular act of heroism inspired Rex to spend years mastering robotic engineering, eventually building a lucrative tech manufacturing empire.
Decades later, Victor finds himself stripped of his company, betrayed by greedy ungrateful proteges, and left bankrupt in the slums. Just as corrupt syndicate thugs move in to finish the old hero off, Rex arrives in an armada of advanced mechanized suits to repay his childhood debt and fight alongside his mentor once again.
