Before the sinking of Atlantis, the ancestors of the Fishermen were once humanoid in appearance. However, after the fall, the Atlantean race had evolved and gained the ability to breathe underwater. On top of that, some gained new appearance and characteristics such as fish-like tails and gills. After this, several splinter factions from the original Atlantis were created and the Fishermen Kingdom was founded.
Orm Marius had a meeting with the Fishermen King Ricou and tried to persuade him into joining him in the War for Atlantis, but he failed. Orm then killed Ricou, coercing his family to join him in the war.
The Fishermen have fish-like characteristics such as scales and a tail, but have human-like hands, faces, and upper torso. They have green blood, and they do not have any hair on their body.
While the Fishermen royal family, due to their highborn status, can also breathe air alongside water, their bodies are not designed for movement on dry land.