Mariners are a human culture and subrace hailing from the cold, barely habitable world of Stygia. Despite significant biological differences, they consider themselves human. The "Mariner" name is an exonym given to them by the surface-dwelling gelugons.
Mariners have perfectly adapted into aquatic life, being able to breathe air and water with equal ease. Because they consider themselves "one with the sea", their bodies host a number of small sea creatures, such as barnacles and starfish. Their skin and hair contain unique pigments otherwise never present in most humanoid races, giving them characteristic teal color which blends well with sea and marine plant life. Otherwise, they are perfectly human.
Mariners have little written history, with writing being fairly alien to them until their discovery by mercane traders. However, one of their greatest mythological poems speaks about their mythic origins, describing their people "walking the earth and the ice, until the sea called them". They are hence believed to have formerly been regular humans changed by their chief god, Rulfengar, who may or may not be a gigantic sea creature elevated to godhood through their worship.
Mariners sailed the seas of Stygia and raided the surface-dwelling cultures with little concept of the greater universe until mercane vessels arrived on the world 556 years ago. Most Mariners still fear the sky, although a small number has taken to aether-sailing as natural sailors. After the Xa'tac War, a small number of Mariner pirates appeared, both in their own bands and as individuals serving ghilani captains.
Stygia and Mariners left behind benefit very little from their space travelling compatriots, barring a few new songs being created about the "heroic adventures of their fellows who sail among the stars".
Mariners are natural sailors and pirates, taking pride in their ability to tame the sea as well as their capability to take whatever they want from others. Mariners have little concept of honor, as understood by most of the Galaxy, and are ruled by a 'might makes right' mentality. Despite this, their sea-bottom society is fairly ordered, with most Mariners leaving peaceful lives of farming seaweed and trading for various exotic trinkets brought from off-shore or off-world. Nevertheless, the few non-pirate Mariners in the Accords Sector are known to be problematic due to lack of taboos about stealing, murder and rape.