There are six planes that form the cosmos. The Material Plane is the one you inhabit. The remaining five are collectively referred to as the Outer Planes.

The scholarly understanding of the Outer Planes is rumored to have once been vast and documented in the libraries and universities of the Old Empire. It is believed by mystics and scholars alike, that most complete research on the Outer Planes may still exist within the ruins of Axion, the once proud capital of The Empire.

Unfortunately, it's also believed Axion was the epicenter of the Cataclysm. A massive Manastorm and large Bloomtides surround the area of the old city. Few people have ever returned from expeditions there in past decades, and those who do are often changed, by the bloom or trauma--their crews lost and never to be heard from again.

The Outer Planes: A Brief Overview

The knowledge of the Outer Planes is limited in this day and age. What is known: the cataclysm ruptured the world's leylines, and these Outer Planes seem to "bleed" into the Material Plane from those ruptures. Interaction with and influence from these planes are often volatile and dangerous. Areas of Bloom have at least one connection to an Outer Plane but can have more than one and in varying degrees. For instance, one area might have a deep connection to the Demonic Plane, and a shallow connection to the Fey plane, causing strange interactions of magics and wilding mutations if you stay too long. Another might have a mix of three or four planes! Rare though that an area of Bloom will have all five Outer Planes influence at once.

The Five Outer Planes

Warlocks and Their Patrons

Warlocks gain their power from powerful entities from the Outer Planes. Whether that is through a deal they made themselves, or brokered by The Wardens of the Sapphire Gate, these entities can potentially be dangerous and often want something in return.
See more about Patron Creation: Warlock Patrons