The Nine Worlds (The Weirkey Chronicles)

The story takes place across a group of nine clustered worlds. Much information is still unknown about them, but this page will gather what is known. There are more references in the current chapters that I didn't track down.

The Nine Worlds
 * Ichil: Dark and cold. Fiyu's home world.
 * Deuxan: Oddly metallic, with an aggressive culture. Primary setting of the second book. One of Theo's original companions was from here.
 * Tatian: The light half is a warm farmland. Nauda was born on the dark half.Primary setting of the first book.
 * Arbai: A dry wasteland world occupied by philosopher golems. Navim's home world.
 * Fithe: A war-like world split between realms of land and water.
 * Slest: Hostile world with a purple sun. Occupied by insects, some of which are humanoid. Primary setting of the fifth book.
 * Siata: A dark world, similar to Ichil, except for "circles", which appear to be columns of light and are with colourful fauna and flora. Has fairy-like habitants with a short lifespan and multiple lives.
 * Aathal: A forested world of sentient trees and deadly plants. One of Theo's original companions was from here.
 * Noven: Bright, with nine suns and many-winged inhabitants. One of Theo's original companions was from here.

Worlds Outside the Nine
 * Earth: This appears to be our planet. Theo and Magnafaor are from there.
 * Cleansed Lands: The mysterious world seen only in the prologue, but is known as a myth in the Nine.
 * Chasm of Lamentations: A roving fragment of a world that temporarily links to others. An essential part of the fourth book.
 * Unknown Eldritch World: The leader and some members of the House of the Lost are implied to be from outside the Nine. They bear at least some resemblance to Lovecraftian horrors.
 * Demon Realm: Demons aren't from any of the Nine, but it remains to be seen if they have a home world.