Zeus is a highly advanced robotic boxer created by Tak Mashido. Zeus is the Robot World Boxing champion, and most robots who stepped into the ring with Zeus never survived the first round. Not only could Zeus autonomously analyze his opponent's moves, but he could rewrite his fighting code to adapt to them.
Max Kenton issued a challenge to Zeus with his robot, Atom, after beating Twin Cities. Zeus's team accepted - much to the surprise of Tak and his business partner Farra Lemkova - and the two robots ultimately fought. At first, it seemed Zeus would pick up an easy win, but Atom made it through the first, second and third rounds. However, Atom's voice recognition software was destroyed midway through the fourth round, prompting Max's father Charlie-a former boxer himself-to utilize Atom's shadow function (allowing Atom to mimic Charlie's moves). Not only did Atom survive the last round, he almost knocked Zeus out.
Zeus was able to get up and not give up, but he was saved by the bell after the final round has ended. The judge's scores gave Zeus the win, but only just. Tak was incensed enough to break the console controlling Zeus, although he still remained undefeated. When asked about his thoughts on the "absolutely humiliating near-loss" Zeus had almost suffered, Tak gave no answer.