The Atlantys core book contains the game rules, background information and a scenario.
The game rules are simple, using a twelve-sided die roll under a character stat to resolve actions. The biggest part of the rules is the description of the numerous Aesthesic powers, which are split in five groups (Energy, Spirit, Elements, Fluids, Body).
The rest of the book describes the world, its different countries and factions, the evolution of humanity, the equipment available to the characters and the human colonies in the solar system.
The book ends with a scenario taking place in a penal colony on the moon.