Zuhl, the one-horned, hunchbacked scientist of the Boazanian Empire, emerges as a pivotal antagonist. Publicly tasked with aiding Prince Heinel during Earth’s invasion, his true objective—ordained by Emperor Zu Zambajil—is Heinel’s assassination. Cunning and brimming with overconfidence, Zuhl designs biomechanical "beast fighters" while secretly collaborating with Duke Zaki to orchestrate the prince’s downfall. His machinations include abducting Professor Kentaro Goh to frame Heinel, though these plans unravel under relentless interference from the prince’s allies.

Zuhl’s aggression intensifies as he infiltrates Heinel’s quarters through concealed passages, only to confront a decoy. Exposed and humiliated, he is coerced into proving loyalty by attacking the Voltes team. Feigning defection to Earth’s forces, Zuhl spins tales of persecution, unaware Heinel has rigged him with explosives to eradicate both traitor and enemies. When the Voltes team disarms the bombs, Zuhl lures them into a trap, but Heinel unveils his treachery. The scientist meets his end at Boazanian hands, his existence expunged from imperial records to bury his shame.

In live-action iterations, Zuhl infiltrates Zardoz’s command as Zambojil’s covert assassin. His manipulative schemes and rivalries with aides Draco and Zandra fuel internal strife. Repeated failures culminate in a fatal confrontation with Zardoz, diverging from the original narrative through altered alliances, physical traits, and motives.

Across adaptations, Zuhl’s arc weaves themes of betrayal and hubris, his stratagems igniting pivotal clashes between Earth and Boazan while exposing the empire’s cutthroat political undercurrents.