Fish-Man

Biodata

Appearance

Fish-Men vary widely in appearance: some have prominent aquatic features, while others look almost indistinguishable from humans 1 3.

• Nereus has no obvious Fish-Man traits; Sebastian has light-blue skin and bright-green patches 1 2.
• A Fish-Man’s fish species is not reliably inherited from their parents, so close relatives can look markedly different 14 202.

Abilities & Skills

Underwater Physiology

• Fish-Men can breathe underwater. Their combat power there is usually several times greater than on land 3.
• Their average arm strength is ten times that of a human, though training can change an individual’s strength 14.
• Their bodies can extract fresh water from seawater, allowing them to survive without a separate fresh-water supply 57.

Fish-Species Traits

A Fish-Man may have an innate ability associated with their particular marine species; not every Fish-Man has an obvious special trait 14 21.

• Arlong can rapidly regrow his shark teeth, while Sebastian can use scorpionfish-like camouflage 14.
• Nanamo secretes a corrosive liquid powerful enough to damage metal 14.
• A small number can communicate with marine creatures 44.

Fish-Man Karate and Jujutsu

These are trained martial arts, not automatic racial abilities. Other races can learn Fish-Man Karate, but Fish-Men and Merfolk generally find its control of water more intuitive 90 262.

• Fish-Man Karate strikes water, including moisture in the air, to extend the reach of blows. Its basic ranged technique, Uchimizu, fires condensed liquid as a projectile 5 14.
• Fish-Man Jujutsu uses throwing techniques to manipulate water, including moisture within an opponent’s body 5.

Naval Combat

• Fish-Men can attack a vessel from underwater without boarding it. Trained fighters can breach or capsize ships alone or in teams 60.
• A Devil Fruit normally removes a Fish-Man’s ability to swim. A submerged user can still breathe but may be unable to escape without help; Nereus’s protective membrane is an exception to the sea’s usual weakening effect 21 306.

History

Fish-Men living beyond Fish-Man Island were scattered among different crews. Nereus sought to draw them together and strengthen the island’s deep-sea defenses against pirates and slave traders 26. After becoming king, he reorganized the Neptune Army and began identifying citizens’ fish-species abilities for military roles 76 78 80. Its First Legion later expanded into a 10,000-member force with companies organized around traits such as electricity, poison, and stealth 131.