The Man-Fish is actually Juan Vallambrosa. He once waged a war against the mysterious mariner Captain X whom he blamed for transforming him into a monster. To this end, he sought out an item known as the Coral Jade, which he intended on using to summon a creature called the Horro to avenge himself against Captain X. At this time, the Man-Fish met the deep sea diving team the Sea Devils. The Sea Devils assisted the Man-Fish until team leader Dane Dorrance discovered that Captain X was in reality his father, John Payton Dorrance. Dane sided with his father and turned against the other Sea Devils. When it appeared as if the Man-Fish slew John Payton, Dane swore revenge against him, until it was discovered that Payton was still alive and that the Man-Fish was innocent. The Man-Fish later allied himself with a being called the Gamemaster in an effort to restore his humanity. In exchange, the Gamemaster wanted the Man-Fish to kidnap Sea Devil Judy Walton. The plan ultimately failed, and the Man-Fish turned against the Gamemaster. The Man-Fish renewed his ongoing agression against Captain X, sometimes teaming up with the Sea Devils - sometimes at odds with them. The Man-Fish later teamed up with a mutated undersea gorilla made out of pure energy. Together, they planned on attacking the surface world. The gorilla was actually the creation of two aliens who subsequently took control of the Man-Fish's mind and ordered him to attack the Sea Devils. Man-Fish managed to break the mind control however to save Judy Walton.
- This version of Man-Fish, including all history and corresponding appearances, was erased from existence following the collapse of the original Multiverse in the 1985–86 Crisis on Infinite Earths limited series. Even though versions of the character may have since appeared, this information does not apply to those versions.
- 5 Appearances of Juan Vallambrosa (Earth-One)
- 1 Images featuring Juan Vallambrosa (Earth-One)
- Quotations by or about Juan Vallambrosa (Earth-One)
- Character Gallery: Juan Vallambrosa (Earth-One)