In the standard cosmology of the Dungeons & Dragons role-playing game, there are seventeen Outer Planes. Nine of those correspond to a specific alignment, or ethical outlook; the remaining eight fall somewhere in between the former. When people on the Prime Material Plane die, their souls travel to the plane that closest matches their perspective in life, to be reincarnated as a new being.
The Archons, Baatezu, Eladrin, Guardinals, Modrons, Rilmani, Slaadi, Tanar'ri and Yugoloths are the predominant species of the nine alignment-specific Outer Planes. Residents of the (good) Upper Planes are called celestials; residents of the (evil) Lower Planes are called fiends. The latter do not menace the rest of the universe as much as they might, as their time and resources are invested in attempting to wipe out each other in a centuries-old struggle called The Blood War.
Each race is divided into sub-races; as a soul proves its merit, it advances from a lower caste to a higher. The sub-races are listed from least powerful to most.
Aasimon / Angels
Unique among the major planar races, the Angels can hail from any of the Upper Planes instead of just one. In 2nd Edition and the Planescape setting, they were called Aasimon. In the first Third Edition Monster Manual they were merely classified under "Celestial" with no particular race name; in the 3.5 revised edition, Astral Devas, Planetars and Solars are reclassified under "Angel".
- Astral Deva
- Monadic Deva
- Movanic Deva
Archons are residents of the lawful good plane of Mount Celestia, also known as the Seven Heavens.
The Angelfire expansion for the D&D Miniatures Game introduced the Justice Archon, while the Tome of Magic: Pact, Shadow, and True Name Magic supplement introduced the Word Archon and the Complete Psion introduced the Sibyllic Guardian .
Baatezu are also called devils. (But note that devil can refer to any native of Baator, not only the baatezu.) Fiendish natives of the lawful evil plane of Baator, also known as the Nine Hells. Though less immediately destructive than tanar'ri, baatezu's blood-chilling yet logical designs reach across the planes and their ranks are perfectly organized.
- Pit Fiend
The Tome of Magic: Pact, Shadow, and True Name Magic supplement added the Logokron to the ranks of the baatezu.
Demodands are inhabitants of Carceri
Eladrin are elf-like celestials from Arborea, also known as Olympus, the plane for the chaotic good.
Guardinals are half-animal celestials of the neutral good plane of Elysium
One of the newer Planar races, the Inevitables (introduced in the Manual of Planes, Third Edition) are a race of mechanical constructs who enforce the laws of the universe. They cohabit Mechanus with modrons and formians, though the former have largely been phased out of third-edition Dungeons & Dragons materials. There are five ranks of inevitable, each responsible for a given universal law:
- Zelekhut — Charged with tracking down those who would escape just punishment
- Kolyarut — Responsible for punishing oathbreakers
- Marut — Seek out those who would cheat death
- Quarut — Maintain the sanctity and inviolability of time
- Varakhut — Responsible for the protection of divine entities from mortal meddling
The Modrons are creatures of the lawful neutral plane of Mechanus, sometimes called Nirvana. Modrons have no concept of individuality and no needs other than serving their part in an ultra-rigid and complicated hierarchy. In first edition, they were magical organic beings, like devils, demons & devas, but for 2nd edition they were changed into biomechanical creatures who could "upgrade" themselves when needed.
- Monodrone - The simplest modrons.
- Quadrone - Can be player characters should they develop individual thought.
- Primus - The ruler of all modrons.
Rilmani are metallic-skinned humanoids of the true neutral plane called The Outlands, or Concordant Opposition. Rilmani believe in maintaining balance, pursuing that end with an alien, unemotional precision.
The Slaadi are froglike monsters from the chaotic neutral plane of Limbo. Although not fiends, they tend to be brutal and merciless with non-Slaadi strangers.
- Mud slaad
- Red slaad
- Blue slaad
- Green slaad
- Gray slaad
- Death slaad
- White slaad
- Black slaad
- Slaad Lord
Tanar'ri are sometimes called demons, but note that demon can refer to any natives of the Abyss, not only the tanar'ri. Fiends from The Infinite Layers of The Abyss, the plane of chaotic evil. Cruel with a passion, they are fiercely independent unless subdued by some greater Abyssal power.
Yugoloths were known as daemons in the first edition rules, but this term has been dropped in later editions. Fiendish mercenaries from the neutral evil plane called The Gray Waste or Hades. Coming in a variety of unpleasant shapes, Yugoloths are infamous for their cold, double-dealing and secretive ways. Most of the Yugoloths have relocated to the Lawful Evil-Neutral Evil plane of Gehenna.
- Guardian Yugoloth