G4

G4 presents as a massive, bulky humanoid machine gilded in glittering ornaments and armor plating, even draped in a regal fur cape and crowned atop its frame. That grandeur is a shell, though; its genuine body is a far smaller robot clad in black plating with softer, rounder contours.

As a machine it feels nothing that might stay its hand, and King's fame as the mightiest man on Earth does nothing to deter it from moving in for the kill.

The robot drops out of the sky into M-City to face King, cracking the pavement as it lands and announcing itself as a machine god of The Organization sent to destroy the world's strongest hero. When King challenges it, a disc on its back unfolds into an enormous sword, and G4 explains that the fight is really a trial run for its combat AI, so a surprise kill would be pointless. Told that King cannot fight at full strength with a full bladder, it grants a bathroom break, threatening to slaughter ten civilians a minute if he fails to return within ten. King never comes back to fight, and when G4 moves on the crowd, Genos shatters its blade in time.

Genos insists on taking the machine alone, hoping the win will lift him into the S-Class top ten. G4 stomps at him only to have its foot punched through, then kicks back onto its thrusters. After Genos hollows out its armor with a blast from within, the plating sloughs away to expose G4's compact true form, which duels him with precise laser fire and severs one of his arms. Genos counters by fogging the robot with fire-extinguisher spray so it cannot aim, binds it with a cable from his own detached arm, and finishes the job in close combat. Its salvaged parts later go to Dr. Kuseno, who repurposes them to upgrade the cyborg's arsenal.