Codex of Demiplanes

THE CODEX OF DEMIPLANES
The following were compiled from the Wizards Planescape boards from entries in 2003 and 2004. This is by no means the final word on these scattered realities. The Demiplane of Zian, Plane of Finite Angles, City of Portal, Onegas' Demiplanar Prison, the Demiplane of Shadows (Alternate) and the Plane of Elemental Wood are listed in separate entries.
THE CODEX OF DEMIPLANES
The following were compiled from the Wizards Planescape boards from entries in 2003 and 2004. This is by no means the final word on these scattered realities. The Demiplane of Zian, Plane of Finite Angles, City of Portal, Onegas' Demiplanar Prison, the Demiplane of Shadows (Alternate) and the Plane of Elemental Wood are listed in separate entries.
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Demiplane of Awe
This Demiplane, also known as the Eden, or Utopia, is the exhact opposite of the Demiplane of Dread, as its infused with Good, rather than Evil, as Ravenloft is. All that is known besides that, of this mysteryious Demiplane is that its influence travels from world to world, seeking the lonely, the lost, and the forgotten, and envelops such beings into itself, giving them a new, contentful existence free from pain, disappointment, or suffering.
To visitors of the Demiplane, a feeling of compassion and love can be felt at all times. Also, visitors and natives no longer age, as Time does not exist here as it is commonly understood.
Finally beings on the Demiplane can leave whenever they wish, unlike in lets say, Ravenloft. Such beings often feel a renewed sense of hope, their lives now feel worth living to the fullest, and their dreams worth pursueing.
Word of Warning: Woe to those of evil bents who come here attempting to work evil. The Demiplane seems to know the intentions of all beings inside of it. Such evil beings find that their existences here become a living nightmare, as the Demiplane inflicts the evils those beings commited back upon them, only one-million fold....
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Demiplane of Anti-matter:
Chant is that on some Prime Material worlds, Fire, Earth, Water and Air are no longer considered elements. On most of these "Scientific" worlds, magic also no longer exists, but on a few, high technology and magic exist side-by-side. On such worlds, everything you can touch and expierence is either matter, or energy, but opposites do exist, and Anti-Matter is just that, the opposite of matter. It is unknown if this belief formed the Demi-plane, or if an insane(And they'd have to be to create this place, see below) wizard created it long ago, but the fact remains that Anti-Matter seems to both exist to challenge the way the inner planes are put toghether, and become a new-inner plane itself. (There are a group of similiar Demi-planes, called the Anti-Inner, which are connected to this plane, which I'll discuss later). Or does this Demi-Plane exist as a weird parrallel to the Prime, like the Anti-Inner do to their Inner Planar counterparts? Perhaps nobody really knows for sure.
Environmental Conditions: If one has the proper protections, Anti-Matter can be "explored" like one might the Inner Planes. With no protection, a visitor will explode as soon as he or she(or it) arrives. All "normal" creatures are subject to this effect, even undead
The Demiplane looks like an average, fertile Prime Material World, but with one exception: All the color is negative. This means that all colors are reversed, including black and white. Visitors to the Demiplane maintain there present coloration, and as such stand out like a sore thumb to the life on the plane.
In the scheme of the Anti-Inner planes, Anti-Matter is the "Prime" of the group. Its formed by a combination of all the Anti-Inner Planes.
Native Life: There are all the creatures one might expect to find on a Prime world here, but with one exception: No magical beasts(like myself I suppose) exist on the Demi-Plane. This means there are no Dragons, no Elves, and nothing else of the sort anywhere on the Demiplane.
Anti-Inner Demiplanes:
Existing to challenge and eventually replace the Inner Planes, the Anti-Inner Demiplanes couldn't be more similiar, or different. Even more confusing is that for every Anti-Inner Demiplane, there is an "Anti-Matter equailiant" or Anti-Anti Inner Demiplane.
Unlike the Inner Planes we Planars know to exist, these Demiplanes are a chaotic mass of unumerial small Demiplanes existing without apparent order or unity. There is one Demiplane for every element that the "Scientific Worlds" have discovered or come up with, so don't be surprised to hear of such places as the Demiplane of Radon or Iron, or even weirder, like the Demiplane of Unioctium. Of particular note is the Demiplane of Gold(which I will discuss later, which is remoured to contain a lost super-civilization similiar to the Azteks(whoever they are).
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The Black Abyss
Not to be confused with The Abyss, The Black Abyss is a demiplane in dissolution into a black hole.
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Demiplane of Banishment (The Forsaken's Final Rest, No-Mans Land):
When wizards want to get rid of their enemies, generally they send them to the Lower Planes, or the Plane of Ooze. But once, long ago one wizard got it into his bonebox that there should be a Plane of Banishment.
Chant is, whenever a wizard casts a spell to send his or her enemies elsewhere, there is a 1% chance that he or she will be drawn here instead. Also, there is a 1 in a Trillion chance that a berk who dies who doesn't serve or believe in a higher power ends up here. This chance increases dramatically on Worlds which have lost all belief in gods(such as Athas). Indeed, on one world this Demi-plane is known as the Grey, and exists as the dropping off point for all cutters who die on that world.
The Demiplane itself is a gigantic city surrounded by a vast, rocky and sandy desert(Like one might find is Arizona, wherever that is), where people who were discarded by the Powers or banished by angry wizards live in a constant state of despair. This isn't like the Grey Waste, where even Hope is leeched from a sod. People live in this state because of each other(There are some shady characters who prey on the weak here) and because of the distant hope that one day, a higher being may take notice of them and save them from their fate. It is said that if one gives up on even hope, than one becomes one of the grains of sand in the desert that makes up the Demiplane.
Native Life:
Other than the sentient bashers on the Demi-Plane, the place is also home to vultures(Who prey on berks who die of thirst in the desert) and scorpions of small and giant varieties. There are other creatures, but these exist as a food source for the Scorpions, or for the living cutters unfortunate enough to be banished here(There is a species of cattle which feeds on the sparse vegetation).
Ways Out:
The Demiplane in no way imprisons those within. Anyone trapped here is doing so voluntarily, or is dead already(For those unlucky souls that have the Demiplane as their final rest, escape is not possible). Any living being banished here can escape, provided one has the means to do so, like Planeshift spells. There are no other ways out of the plane other than magic, so unless one happens to be a Wizard or Priest(Or has one handy nearby) they might have to think about becoming permanent residents.
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The Isle of the Ape
(from the classic module of the same name). Also run by the prankster-god Zagyg, this is a jungle demiplane dominated by dinosaurs and oversized primates. The fabled crook of Rao was hidden here. A portal exists within the castle of the archmage Tenser.
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The Isle of Black Trees
(mentioned in the Eternal Boundary Adventure in the Planescape line). Perhaps a vista of black monoliths, with roots that extend into the near ethereal inhabited by strange parasites. Possibly created by feuding academies of wizards, and conceivably part of the long khaasta trading route between Pandemonium and the material plane's Vale of the Mage.
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The Boundless
A demiplane of ocean and crystal isles. The Demiplane heals 1st time visitors, restores youth of 2nd time visitors, and permanently traps 3rd time visitors.
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Demiplane of City:
Imagine every city on the Prime(From every known technological era) and then imagine them all merged into one giant, Demiplane size realm, and you've got the Demiplane of City. The natives(All human) no of nothing outside their city-realm(And forget about it soon after learning about it). If one likes crowds(And there are ALOT of them here) than this place is paradise.
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Court of Rings
(From the From the Ashes boxed set). A faerie realm, fading from the reach of the Material Plane. The Cat Lord is also said to hunt here.
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The Crypts of Iron Souls.
(Greyhawk: From the Ashes) Another fading land, this demiplane is stocked with undead, semi-liquid ash and bone, and physical screams that can burn and wound.
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Draedenden
A starless void full of maggots ten kilometers in length. This is probably a nest left by the enormous entities known as Draedens, whom some say are ancient enemies of the gods.
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Demiplane of Dread:
AKA Ravenloft. Not much is known about this Demiplane, which is often confused with the Demiplane of Imprisonment, other than that is is NOT pleasant.
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Demiplane of Dreams:
Where the minds of Primes(and perhaps Planars as well) go when they dream. This Demiplane has no form to speak of, unless a Prime Mind is present to give form to the chaos of the Demi-plane. It is also sometimes regarded as the third "layer" of the Ethereal Plane.
Interesting Note: Where regions of the Demiplane are enveloped by the mists of the Demi-Plane of Dread, exist the Nightmare Lands.
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The Deathdark.
("Wild Elves") A demiplane connected with the world of Krynn and home of Jiathuli, an imprisoned Handmaiden of Takhisis.
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Dungeonland
(From the module of the same name). Another of Zagyg's play-dimensions, this demiplane is accessible from the ruins of Castle Greyhawk. It contains sinister mad hatters, jabberwockies, and other unusual monsters.
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The Mines of Dumathoin
(Greyhawk: From the Ashes) A fading land created by the dwarf god Dumathoin full of sentient gems, gas, mining tools, and pit traps. Doubtless also the home of the urdunnir.
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Demiplane of Eions:
This weird place imbodies the ever evolving technological and culturally changing humans of a long-lost Prime world. It is believed that this Demiplane was orginally a cosmic museum(Or cosmic Time Capsule) of some sort(The golems built to look and act like natives of each time period presented may support that theory), and that it has been abandoned for untold millenia. Regardless, the Demiplane of Eions is a curiousity and diffenitely a wonder of the planes.
The Demiplane is lade out in a linnear fashion. If one were to walk from one side of the Demiplane to the other, one would pass threw primitive villages of cave-dwellers, primitive cities made of clay, huge monuments to Gods and Kings, breath-taking citys and monuments made of Marble, and cities and fortifications made of stone(Most Prime worlds resemble this section of the Demiplane). The Demiplane continues however, with more and more advanced technological cities.
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The Elemental Nodes.
(From Temple of Elemental Evil} These are semi-planes of elemental matter linked to the fearsome temple of Elemental Evil.
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Demiplane of Ectoplasm
See http://www.wizards.com/default.asp?x=dnd/psm/20030725a for details on this Demiplane
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Demiplane of Fairie:
A relatively new Demiplane created by Queen Titania of the Fairies to serve as the new home of the Seelie court and Fairie-kind away from Arvandor and the Elven realms of Arborea. The Demiplane is large enough to be considered a full-fledged plane, but is still considered a Demiplane by stubborn Planar scholars(Like myself).
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Demiplane of Fear:
A relatively unknown Demiplane connected to the Prime world of Mysteria.
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Demiplane of Frost
A tundra-like Demiplane often confused with the Paraplane of Ice, has few inhabidants, most notably the Frost Wolfs(See Mimir.com). Not to be confused with the fabled Quasi-Para Elemental Plane of Frost.
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The Demiplane of Flowers/Quasi-Elemental Plane of Flowers
(WG7: Castle Greyhawk). A vast green place filled with every species of flower imaginable, and many that defy imagination or comprehension in size, shape, and color. Popular with giant bee-creatures and beelike humanoids such as the abeil. Theorized by some to be the quasi-elemental link between the Elemental Plane of Wood and the Positive Energy Plane(If wood is in fact, the fifth element, than this is likely true)
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Demiplane of Haven:
A small city Demiplane resently created by the Mercanes to compete with Sigil as the Hub of the planes. [See also: City of Portal]
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Gargantua
A featureless Demiplane of Giant humanoids the size of planets. If one can communicate with them, they will find that the creatures are fairly lacking in intelligence(Which is surprising, considering there size)
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Demiplane of Gold:
An entire jungle Demiplane composed of Gold. The Demiplane of Gold would be the site of the largest gold-rush in Planar history if it weren't for the advanced natives, a human-like race of superior magical might than any wizard of the Prime, with a culture resembling that of Pre-Columbian Mesoamerica(Wherever that is). Chant is that the native's Ziggurats contain artifacts of untold magical power strong enough to defeat and protect against even the Lady of Pain. One thing is for sure, the natives aren't talking about it to visitors anytime soon.
The Natives view all visitors as intruders, and so many have dissapeared that few try to go to the Demiplane anymore. It is said that the natives sacrifice intruders to their mysterious gods in exchange for the massive powers they possess.
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Demiplane of Gravity:
It is said that what goes up, must go down, but on the Demiplane of Gravity, pretty much nothing moves. This Demiplane has the dubious honor of being the resportory of Gravity for the Planes, and as such, is like one big enormious Gravity Well. Nice to talk about, not nice to visit(I can tell you that from expierence).
Despite attempts by berks like members of the Downguard Sect(A group that believes that gravity as it acts on the Prime should apply everywhere) there exist no structures, no citadels, and no lifeforms of anykind on the entire(and its a BIG) demiplane.
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Demiplane of Groggor
This half-world has a runaway greenhouse effect - the atmosphere is dense, and foggy, the surface dark and treacherous, a mass of endless boiling mud. Shallow, pulpy mounds are the only solid ground. These mounds are sentient creatures called groggors hundreds of feet tall, although nearly all their height is buried in the mud. Like whales, they are social philosophers of the deep who communicate via low-frequency symphonies of a muddy, burping nature. The groggors, with their advanced intelligence, know something of the nature of the other planes of the Multiverse.
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The Ghost Sea
Also known as the Phantom Ocean. This spiritual, ethereal sea is the final resting place for whales from an isolate Prime Material World. Not much else is known about this Demiplane
-From Mazaron's Monstrious Manual
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Demiplane of Holes:
This curious Demiplane has no real rythym or reason. It is simply a massive white expanse dotted with black colored holes as far as the eye can see.
If a cutter puts his or her hand in one hole, chances are it will emerge from another hole nearby. Its disconcerting at first, but the effect(perceivebly) is harmless.
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Demiplane of Illusion
A Demiplane supposable which is the origin of all things Illusion. Most things here are simply illusions, and only can be seen. Some Illusions, however, are so realistic that they cause actually damage, and some Illusionary creatures are in reality, intelligent. A trip to Illusion can drive a sod barmy quickly, as the line between Real and Unreal becomes blurred fast.
One sinister rumor speaks of Illusionary beings with the power to cause real beings to become illusions, effectly switching existences with their victims.
Like the Demiplane of Mirrors, Illusion should be avoided.
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Demiplane of Inphirblau:
The City-realm of the Phirblas, weird humanoid creatures similiar to the Dabus of Sigil.
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Demiplane of Imprisonment:
A Demiplane of which is known even less than the supposed Demiplane of Dread. May possibly contain the Elder Elemental God within...
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Demiplane of Infuma
A null-magic plane dominated by steampunk dwarves in airships, Victorian automata, and polluting factories as far as the eye can see. A druid's worst nightmare.
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The Demiplane of Knowledge
This unusual Demiplane appears like a-nearly infinite libruary of Books and Scrolls. It is a place where almost any question about any topic can be anwsered, for a price.
Any time someone wishes to partake of the knowledge this Demiplane has to offer, he or she must give knowledge back to the Demiplane, for example: A mage wishing to learn a forgotten spell, must give one of his or her' orginal or rare spells to the Demiplane, the knowledge concerning the payment is lost to the individual in question, with no refunds.
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The Demiplane of Knowledge Concerning the Layers of the Abyss and Carceri
(WG5). Pretty much how it sounds - a contemplative place of lore and secrets of the most hateful of planes.
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Demiplane of Labyrinth:
Somewhere floating in the Ethereal is an enormious near-infinite maze known as the Demiplane of Labyrinth. Unlike one of the Lady's mazes, this maze is composed of an indescruptable stone-like substance, and is lade out in the forms of walls laid out in strait angles(picture one of those classic mazes you used to do for fun on the back of cereal boxes, whatever that is). It is said that a cold, sinister intellegence studies those who end up here(Usually threw accidents in Planar travel), as they try to escape.
Time ceases to flow for a sod unfortunate enough to end up here, which gives anyone trapped here an eternity to find his or her way out. One cannot permanently die here either, and anyone who tries to commit suicide, will find themselves resurrected the following day, none the worse for wear back where they started in the maze.
Along with the twists and turns of the maze, weird round-one eyed monsters wander the maze and devour anyone they come across(Again, anyone killed will be resurrected and returned to his or her starting location in the maze).
There is only one exit for this plane, the bad news is that its in the exact center of the maze.
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Lopado
(Full name: Lopadotemachoselachogaleokranioleipsa
nodrimypotrimmatosilphio paraomelitokatakechymenokichlepiko ssyphophattoperisteralektryonop tekephalliokigkropeleiolagoiosiraiobaphe
traganoppterygon)
An ocean of air where giant bacteria float about, feeding on other giant bacteria. The bacteria have an incomprehensible philosophy and mostly untranslatable language based on that philosophy (although the name of the plane has been tentatively and extremely roughly translated as "happyhome" - this doubtless does an extreme injustice to the advanced philosophical concepts involved.) The bacteria have created many cubic gates, unfortunately keyed to their language.
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Demiplane of Lost:
When one loses a personal (or stolen) possession, chances are it ends up here. Also known as Unsoncy in some circles.
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Lost Citadel of Magic
Demiplane realm of the 3 gods of magic from Krynn (the world of Dragonlance).
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Land of the Immortals
Demiplane realm of various Chinese gods dwelling outside of Mechanus' Celestial Bureaucracy.
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The Moonarch of the Sehenine
(From the Ashes}. A testing ground for elder elves seeking to move beyond the mortal lands to the Far Isles of their destiny.
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Demiplane of Mirrors
Another oddity of the planes. The Demiplane of Mirrors is a truly bizzarre realm of reflections, and the mirrors that spawn them. Some mirrors reflect the truth. Others distort them, and some of those distorting mirrors cause those gazing on them forms to match the reflection(Very creepy). Still others reflect the truth, but in reverse(An evil Paladin, a good or living version of a lich or other undead). Other, still rarer mirrors serve as portals to "Mirror Universes" where everything is similiar to the normal Multiverse, but in reverse(Evil Upper Planes, Good Lower Planes, Fire is Cold etc).
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Demiplane of Morcellate
A void, which was once part of the Prime. It is full of planets and stars, the only intelligent race here is a lost armada of planar spiders. They search for a portal leading to the fabled Prime Material Plane, which they consider to be a purgatory they must enter before they reach their eternal reward.
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The Lady's Mazes:
When one provokes the Lady of Pain, one of the possible outcomes is to end up in a maze, a tiny self-sustained demiplane.
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Demiplane of Machines:
This to-be-avoided Demiplane is really(mostly anyway, since they are the main inhabidants) an enormious extradiamensional Sheen hive resembling the hardrive of a computer found on an unamed Prime World with a sky full of gears which look like they came straight from Mechanus.
For the ignorant, the Sheens are a race of extreme-high tech artifical lifeforms possessing a hive-mind and possessing insect-like, but alien forms. They range from the tiny Scouts to the fearsome Render, and generally attack all who end up on the Demiplane.
Chant is, all artificial lifeforms(Like Clockwork Horrors and Triobond's Automatons) somehow end up here after their descuction on the Prime Material Plane.
An interesting Note:
There exists a colossial Machine Empire, if you will, somewhere on the Demiplane independent of the Sheens. These beings resemble humans but are composed of clockwork and metal, and have a very hostile attitude toward organic lifeforms, which they have vowed to destroy threwout every Plane of existence(nice guys huh?). It is totally unknown why these "Machine-Men" have a hatred as deep as it seems to be, but regardless, nobodys going to ask them and return to tell the tail anytime soon.
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Demiplane of (Electro) Magnetism:
An entire Inner Planar-like Demiplane built entirely around the concept of magnetism. Berks composed of metal, wearing metal, or carrying metal, BEWARE!
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Demiplane of Maelost
Also known as the Ridged Land, this Demiplane mostly consists of black rock ridges and rainfall aplenty.
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Demiplane of Moil
A city from the Prime World of Ranais that was trapped in a demiplane by Orcus (c.f. Dead Gods adventure). Inhabitants are primarily ghouls, ghasts, wights, wraiths and the undead creatures known as the Lovelost. Not all the undead are hostile. Moil was the capital of an empire that worshipped death, genocide, undeath and specifically Orcus, Demon Lord of Undeath. As a reward for their fine service, Orcus killed all the inhabitants of this world. At the centre of Moil stands The Black Temple, sepulchre to ultimate evil and mass murder.
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Demiplane of Numbers:
A downright bizzare Demiplane where everything is composed of well, numbers. Everywhere you look on this white Demiplane you'll see numbers hanging in midair(The Demiplane possesses no Gravity). Thing is, every possible number(Even Negative and decimal numbers) exist here as floating objects of varying sizes(The bigger the number, the bigger the object). Generally, numbers like 1 or 10 are small enough to fit in the palm of a human hand, while numbers like 1000000 are large enough to live inside, and incomprehendably large numbers like Google or Google-Plex are continent or world-sized. Meanwhile, Negative numbers exist on an ever-decreasing microscopic level.
One wonders how an infinity of numbers can fit on a finite demiplane. Perhaps because the Demiplane of Numbers is both Plane and Demiplane? Or maybe its just the nature of mathamatics, and loopholes exist to create such a paradox. Regardless, the place is a mathmatician's paradise.
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Neth, the Living Demiplane:
Supposedly there exists a Demiplane which is in reality an entire living creature, who knows?
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Demiplane of Nightmares
Very unpleasant Demiplane that serves as a dark twin to the Demiplane of Dreams, not to be confused with the vastly similiar Nightmare Lands of Ravenloft. Has a mysteryious connection to the Prime World of Mysteria(Of the campaign setting of the same name). This is a horrific place where the dimensions are distorted and mortal magic is impossible. Everything on this plane is poisonous to normal life. The inhabitants include neh-thalggu, feyrs, and the fiendish-looking diaboli. Apparently the natives of the demiplane find Material Plane natives as horrific as we find them. This may also be a misinterpreted record of encounters with the Far Realm.
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Newmarket
A 36-level dungeon Demiplane inhabited by wandering mortals from the Prime Material Plane.
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Demiplane of Nubilate
An air-dominant demiplane inhabited by air elementals and djinn. Without the interference of the elemental rulers, the elementals have grown to amazingly vast sizes. The djinn are trying to keep them under control, but are well on the way to being overrun by enormous, wild, restless, starving elementals of air and wind.
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The Prison-Fortress of Onegas the Heartless
Enormous Demiplanar prison of a being of immense power known only as Onegas the Heartless (See separate entry for detailed information)
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Demiplane of Pyx
Another planet-strung void, inhabited only by a group of lost, masterless Meks (ancient robots, similar to sheens) destroying all intruders in the vain hope that one of them is responsible for the death of their creator. Is linked by a portal to the Demiplane of Machines.
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Partheniad
A jungle Demiplane of amazons and sibyls, to whom men are fit only for domestic servitude. A Goddess named Mazikeena occasionally comes to this Demiplane and tries to persuade them to change their ways, but they ignore her for the most part.
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Pavilion of Cynosure
Neutral ground for the greater gods of Faerun (of the Forgotten Realms setting).
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Rocta
A featureless demiplane filled with mysteryious crystalline creatures known as Jumpers.
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Ravenloft Elemental Planes
Where the Demiplane of Dread intersects with the four core Elmental Planes, four unusual - and slightly disturbing - Demiplanes are born.[See separate entry for details]
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Demiplane of Semblance
Haven and hide-away for group of wizards called the Mhagane.
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The Shattered World
(1st edition Manual of the Planes)
Once a world of the material plane where the level of magic was so high that every wish of the inhabitants was instantly fulfilled. Inevitably, the world broke up into an archipelago of demiplanes, each dominated by an all-powerful demiurge. To Be Avoided.
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Demiplane of Serpentia
A Demiplanar jungle world filled with colonies of yuan-ti who dominate a race of humans with no magical talent or sense of adventure. The humans are, naturally, in retreat. Each yuan-ti colony is led by a group of elders schooled by an avatar of Mazikeen in the magical arts. The yuan-ti call Mazikeen Stirpicore, and revere him as the savior of their race. They depict him as a giant yuan-ti, the form his avatar takes on this plane. Their culture and that of the hapless humans is somewhat Mesoamerican in style
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Scriniari
Featureless Demiplanar home of telepathic, microscopic beings called Brownians who feed on patterns and data.
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Splacknuck
A dark, cold, watery demiplane inhabited by fragile, intelligent bubbles. They feed on magic(which exists as raw, stable force threwout the Demiplane). Any source of heat or light harms and eventually destroys them.
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Demiplane of Sides
Most, if not all areas of the multiverse exist in all three spatial diamensions, the same holds true for the Multiverse' inhabidants. However, there exists lifeforms, such as the Diamensionals (http://www.mimir.net/monsters/dimensional.shtml) that exist in less, or even more than three spatial diamensions. The Demiplane of Sides is a Demiplane that only has 2 spacial diamensions, but does not impart its duality on all three-diamensional visitors.
For beings of three spacial diamensions, imagining a 2-D existence is nearly impossible. But I can at least attempt to explain it a bit.
Imagine a flat-paper, now imagine yourself on that paper. Basically, you exist as a three diamensional being existing on a two-diamensional backdrop. That is the Demiplane of Sides in a nutshell.
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Demiplane of Time
The Plane which is the source of all Time, or continuity. This Demiplane has a collection of bizarre and deadly inhabidants, such as Time Diamensionals and Vortex Spiders, as well as adopted protectors, mysteryious wizards know as Chronomancers......
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Demiplane of Thorns/Quasi-Elemental Plane of Thorns
If the Demiplane of Flowers can said to be the Elemental Plane of Wood's link to Positive Energy, than the Demiplane of Thorns is its opposite, a Plane(or Demiplane) spawned between the endless Entropy of the Negative Energy Plane, and the endless Green of Elemental Wood.
The result is this place of endless black vines all baring thorns of varying degrees of sharpness. The closer one gets to the Negative Energy Plane, the sharper the thorns become. In the distance, in addition to seeing enormous vines of thorns, some of which may be continent-sized, one also catches glimpses of green clouds. These clouds are not natural, but the product of one of the Demiplane's natives, a cactus-like creature of which little is known.
Of note: The Queen of Air and Darkness, of the Unseelie Court, sometimes dwells in one of the more evil-looking areas of the Plane/Demiplane. As a result, evil sylvan races of all kinds can be found on this Plane/Demiplane, in addition to the Demiplane's/Plane's natives.

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Thoke
A dead plane of wreckage and ruin, destroyed long ago by planar marauders (the draeden). Possibly home to forbidden knowledge once capable of hurting those marauders.
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Wormscape
Demiplane of, well, worms. Not to be confused with the "Worm Realm" of the Abyss
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The Land of Webs and Caves
(Mystara Monstrous Compendium; Spider-kin]. The secret demiplane of the planar spiders, a race of evolved phase spiders who explore the many worlds of the Astral and Ethereal Planes. The best-known nation in the demiplane is called Chak.
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The Warren
A Demiplane sized, underground complex where humans are dominated by an intelligent, but quite mad, machine. Magic is outlawed, and the humans are paranoid, attacking extraplanar visitors on sight.
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Demiplane of Urunaland
A Demiplane in progress so to speak. This place is a manually constructed demiplane by a group of dwarves.
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The Maze of Zagyg
(from Treasures of Greyhawk). This is a maze of ethereal protomatter. It recedes in the distance the closer you come, and seems to get bigger the further you move away. The hiding place of an artifact, the sinister Face of Xenous.
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Thorne
A portal on the world of Mystara (lying beneath Lake Avernus on the Island of Dawn; its key is a relic known as the Periapt of Pax) leads to the plane of Thorne, a realm heavily influenced by the proximity of the Negative Energy Plane. The terrain is nothing but living thorns the size of mountains, each of which branch into vast forests of somewhat smaller thorns. Its primary inhabitants are phanatons - monkey/racoon/flying squirrel creatures - and their allies, an advanced race of phase spiders. They live in platform villages made of thorn lumber and webs.
In a fortress of thorns a vampire, the ancient pharoah Ramenhotep X (vampire monk 15), and his demon bride Aketheti, Daughter of She-Who-Dwells-In-Darkness, dwell with their undead servitors, terrorizing the locals and the planes beyond.
Thorne Traits:
- Normal Gravity
- Flowing Time: One hour in the Material Plane equals ten hours in Thorne.
- Finite
- Alterable Morphic
- Enhanced Unlife: Undead are turned or rebuked at half the cleric's level.
- Normal Magic
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Chasm
A portal in the demiplane of Thorne leads to this world, a place of nothing but steep cliffs and the gloomy, freezing, windy abyss in between.
The Dark Tower is a two mile-high fortress built at a right angle to the walls of the cliff. The Tower distorts time: one hour in the Material Plane is equal to 1000 hours in the Dark Tower. The Unholy Transformation trait affects one hit die every six hours, rather than every twelve hours as in the rest of the plane, and the DC to save is 20. Beneath this tower is massive labyrinth called the Night Maze.
Other than an undead black dragon and some oozes, the only inhabitants of this plane are a race of skeletal undead with long white hair called reveners, whose touch steals the senses of sight, taste, hearing, touch, smell, or psionic aptitude from mortals, and a race of goblin-like constructs called duskers with the ability to transform their opponents in ghastly ways.
Chasm Traits:
- Heavy Gravity
- Flowing Time: One hour in the Material Plane equals 100 hours in Chasm.
- Finite
- Alterable Morphic
- Enhanced Unlife: All turning and rebuking effects fail in this plane.
- Unholy Transformation: Mortals in this plane have the positive energy in their bodies replaced with negative energy at the rate of one hit die every twelve hours (Fortitude save DC 10). One way to handle this might be to replace a character's existing levels with Savage Species-style levels as a death knight, vampire, or lich.
- Impeded Magic: Healing spells heal only one hit point per die.
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The Isle of Night
Created as a vile mockery of Mystara's Isle of Dawn, the Isle of Night is a barren, desolate home of dead vegetation and undead. A portal to this plane is found within the Night Maze of Chasm; it's key is the solution to a puzzle involving all six senses.
The Isle of Night is ruled by nightshades and their evil queen, known as the Night Spider or She-Who-Dwells-In-Darkness. Sentient zombie slaves under their thrall are driven by more powerful undead to build purposeless edifices of titanic size. These zombies are "bred" by their masters in stinking pits as the old ones are worn out or mutilated beyond repair; whatever remains are left are thrown back into the pits to create the next generation.
The most prominant feature on the plane is Night's Watch Plateau, which is over two miles high. It also contains towns full of undead, dead forests, hills, mountains, steppes, and lifeless rivers and seas. A black 3000 square foot monolith drifts slowly through the skies; it is a living entity from Mechanus on business of its own.
In an ancient metropolis lie entombed a king and queen from the Material Plane; it is from their flesh that the first zombies were seeded.
Atop Night's Watch Plateau is a portal to the Material Plane; its key is an artifact, which the portal will ultimately destroy in order to fuel itself.
Isle of Night Traits:
- Heavy Gravity
- Flowing Time: One hour in the Material Plane equals 10,000 hours in Chasm.
- Finite: The Isle of Night is probably no more than 100 miles in diameter.
- Alterable Morphic
- Enhanced Unlife: All turning and rebuking effects fail in this plane.
- Unholy Transformation: Mortals in this plane have the positive energy in their bodies replaced with negative energy at the rate of one hit die every three hours (Fortitude save DC 30). One way to handle this might be to replace a character's existing levels with Savage Species-style levels as a death knight, vampire, or lich.
- Impeded Magic: All healing spells cast on this plane fail.