Far Realm

In the Dungeons & Dragons role-playing game, the Far Realm is an alien dimension of cosmic horror. It is the home plane for many aberrations and strange monsters.

The Far Realm's mix of horror, madness, and strange geometries was largely inspired by the work of American writer H. P. Lovecraft.

The Far Realm is particularly inspired by Lovecraft stories like "Through the Gates of the Silver Key."

The Far Realm was created by Bruce Cordell, and introduced in the second edition Advanced Dungeons & Dragons adventure module The Gates of Firestorm Peak (1996).James Jacobs later called Cordell's work an "adventure with a distinctly Lovecraftian feel", noting that "Deep inside Firestorm Peak lies a portal to an insidious region beyond sanity and light known only as the Far Realm, and the unknowable but hostile entities of this hideous region prepare to pass through into the world." The adventure featured a magical portal that produced creatures and energies from the Far Realm.

In third edition, the Far Realm was incorporated into the Realm of Xoriat in the Eberron campaign setting.

In fourth edition, the Far Realms were included in the new cosmology design of Dungeons & Dragons. In this edition, members of the Warlock class can forge a pact (called the Starpact) with the entities from or near the Far Realm in order to gain power. The Far Realm's association with the new setting has been detailed in various supplements.

The Far Realm contains an infinite number of layers, these layers range from inches thick to miles, and it is often possible to perceive multiple layers simultaneously. These layers can grow, spawn further layers, breathe and possibly die.

The Far Realm is home to many powerful and unspeakable beings ripped from the nightmares of the darkest minds of the waking world, beings so unfathomable that their very existence is a perversion of reality itself. These beings are governed by lords of unimaginable power and knowledge completely alien. The Far Realm is a plane far outside the others and often not included in the standard cosmology. It is sometimes referred to simply as "Outside", because in many cosmologies it is literally outside reality as mortals understand it.

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Wikipedia