Return of Hadrach
The exact structure of the Outer Planes are a matter of great debate among the scholars of Yerth.
Some believe the outer planes are structured like an unimaginably vast onion, with the Prime Material plane at the core. Each additional plane surrounds the previous, and with the inclusion of the Abyss, it stretches into infinity.
Others believe the planes to be structured like a vast wheel, each plane acting as a kind of spoke, the center axis being the Prime Material plane.
A third doctrine believes each plane to be a self-contained location floating in the vast Astral plane
There is evidence for and against each of these theories, not the least of which are the various interpretations of the Sanctioned Laws, and Planar scholars are rather evenly divided as to which theory is the most accurate.
There are 9 Primary Outer planes:
Abaddon (Neutral Evil)
Home of the daemons, fiends of pure evil untouched by the struggle between law and chaos, who personify oblivion and destruction. Daemons, which are ruled by four godlike archdaemons, are feared throughout the Great Beyond as devourers of souls.
The Abyss (Chaotic Evil)
Spawning ground of the innumerable races of demons, among the oldest beings in all the Great Beyond.
Elysium (Chaotic Good)
Freedom and self-sufficiency abound here, personified in the azatas native to the plane.
Heaven (Lawful Good)
Heaven’s native archons see law and good as indivisible halves of the same exalted concept, and array themselves against the cosmic perversions of chaos and evil.
Hell (Lawful Evil)
Hell is divided into nine nesting layers, each under the malevolent rule of an archdevil.
Limbo (Chaotic Neutral)
Limbo’s native proteans cavort in the Primal Chaos, creating and destroying the raw stuff of chaos with unfathomable abandon.
Nirvana (Neutral Good)
Nirvana’s native agathions have willingly postponed their own transcendence to guard Nirvana’s enigmas.
Purgatory is home to the aeons, a race who embody the dualistic nature of existence and who are constantly both at war and at peace with each other and themselves.
Utopia (Lawful Neutral)
While no one race rules Utopia, axiomites and inevitables make their homes here, forever striving to expand their perfect city.
In addition, there are numerous Secondary and Demi-planes