Chaos Plane, Fortress Celestia (3.5e Environment)
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The Fortress Celestia setting is a battle between lawful evil and lawful good, with both sides consuming, and being diluted by, planes of chaos, the forces of lawful evil out of a need for conquest and victory, the forces of lawful good out of a combination of necessity and convenience. The chaos plane was the one that got away. Of all the planes remaining in this postapocalyptic multiverse, the chaos plane ironically has changed the least from its original form.
The chaos plane bears a strong resemblance to the transit plane. On both, Islands of solid matter and other debris pepper a seemingly infinite void, but whereas the transit plane is mostly unchanging, the chaos plane is almost always undergoing massive changes. The Chaos Plane has no permanent structure, no layers, demiplanes, and no famous monuments or cities. Such things can exist here, but typically they do not do so on a permanent basis. This is a universe where time and space have little meaning, and maps are all but useless, for the location of things that would be famous landmarks elsewhere can change completely from day to day. The normal laws of physics actually do exist here, but the plane only bothers to follows rules when it feels like it.
Much of the air is quite breathable, but there also regions where the voids are cold hard vacuum. The sky can be any color, and often the sky appears cloudless. Yet even in the calmest places, the sky is churning with change.
 Plane Traits
 Physical Traits
Highly variable, mostly subjective. In much of the plane, there is no gravity. In other places the gravity is changing constantly or in a completely illogical direction. Most places, it is possible for sentient beings to mould gravity locally with their mere thoughts, but such changes rarely last.
Highly variable, yet often normal. Time can flow at any rate it pleases, usually flowing at different rates at different places or times, and occasionally flowing backwards in places.
Infinite, or at least seemingly so. Most of the time, anyway. Size and distance have little meaning here.
highly morphic. Most places, it is possible for sentient beings to mould space and matter locally with their mere thoughts, but such changes rarely last. Sometimes, the plane does what it wants anyway.
 Magic, Alignment, and Energy / Elemental Traits
 Elemental Dominance
None. However, the predominant content here most often is a gaseous void, in which drift various solid forms.
 Energy Dominance
None. However some regions are strongly positive or negative.
 Alignment Trait
None. However some regions are may occasionally be strongly aligned.
 Magic Trait
None. Occasionally, magic doesnt work at all, or works in very non - normal ways.
 Movement and Combat
 Features of the Plane
The chaos plane has no clearly defined structure. Instead certain regions can appear to become layers, at least temporarily. However, these are really just immense regions, not separate layers or demiplanes. Some exist only for a moment while others can persist for millenia. Sometimes a pseudolayer is destroyed only to reappear years later. Sometimes, the individual pseudolayers seem to be as large or larger than the plane in which they reside.
 The Heart of Chaos
Also called the Maelstrom, this phenomena typically appears an immense churning storm that is constantly changing its position, shape, size, composition, etc. Inside, the laws of physics change from moment to moment. Many inhabitants live their lives terrified by it. Many who enter never return, and many who do come back scarred or horrifically altered in some way. On occasion, it leaves plagues of locusts or other such creatures, bizzaroids, or lovecraftian monsters in its wake. Usually it appears as a world - sized multicolored firey explosion frozen in size but still churning with energy, but it can suddenly expand to snatch creatures and objects from the plane, or transform itself into something ordinarily, only to reform moments later. There are no random tables for the Maelstrom; it does as its own whims take it.
 Quet Zones
These regions feature a milder form of chaos, allowing civilization and stable ecosystems to flourish, or at least exist over reasonable long historical periods. The Maelstrom appears in these areas less often.
 Debris fields
These regions are filled with random objects, from paperclips and socks, to winged monkeys juggling cream pies, to gears and mile - long machines bent and ripped in half by unknown forces. Some are quiet zones or pseudolayers.
These pseudolayers resemble outer space in the real world. Some are said to house actual stars, planets, and even spacefaring civilizations.=====Islands===== Islands of other stuff drift in the void, but they are far more varied than those on the transit plane. Category 5 hurricanes drift in the void with no land or water for a thousand miles around them. Raindrops larger than cities support their own ecosystems. Spare gears from the Broken Machine rotate as they drift in formation.
 Plane Links
The chaos plane has always been home to an illogical assortment of creatures and creature - like phenomena. 'Always chaotic' - aligned Outsiders, bizzaroids, lovecraftian horrors, and mostly harmless oddball vermin and animals are the typical inhabitants, if any inhabitants could be considered typical. Other inhabitants include natives of pieces of worlds and planes that became islands and refugee races with access to interplanar magic.
 Planar Politics
Most people who live here are usually too busy either trying to go somewhere else, survive, or act in a way lawful beings would consider silly to worry about what is going on in the other planes at the moment. A few care very deeply however; some are even agents of one of the planar nobles sent here on some fools errand in hopes that it could somehow affect the war effort. In reality, except in the quet zones, nearly everyone here is lost, and will be lucky if they ever find their way home. Fortunately for many natives, they simply don't care.
 Random Encounter
flip randomly through any book, website, etc. with random encounter tables and pick one. Whatever it is appears. Maybe around the corner or falling sideways out of the sky.
 Chaos Police
some mentally unstable humanoids or low - CR chaotic - aligned outsiders are going arround 'arresting' and 'sentancing' others for following rules. They are quite serious about their work, but of course are being careful not to follow any reason or logic in who they choose to arrest or what sentance to hand out. They might sentance a party member to being urinated on for failing to betray the others, then order the party to wait for their sentance to be carried out while they call in backup to confront a blade of grass.
a party of low - CR lawful - aligned outsiders are attempting to make their local area of the plane as orderly as possible, in hopes of establishing a foothold for their fellows to invade. They will react poorly to any attempts by the player character to convince them that their efforts are futile, if the characters break any of their 'laws', etc.
 Rebels without a clue
a party of chaotic - aligned humanoids or low - CR outsiders working for an ambitious but foolish higher level cleric or outsider planning a revolution against some authority, perhaps a planar lord or maybe even something that only exists in the group's imagination. They might attack any player characters they encounter, welcome their long lost allies, pretend to be something else in hopes of spying on them, or attempt to debate them.
 Survivor shantytown
a tiny town in the middle of nowhere, obviously hastily built from whatever supplies people happed to have. The community is obviously very impovershed, but some citizens wear scaps of fine clothing. Many bear the scars of old injuries. They seem surprisingly friendly, almost intimate, with each other despite being of species, politics, and / or religion that would normally not make good friends. It soon becomes apparent that they are the survivors of some horrific disaster. Maybe they are all that remains of a proud civilization, trading fleet, etc. that was swept into the maelstrom or destroyed by an outsider army. They might welcome the player characters as fellow survivors or suspect that they had something to do with their fate.
 Demon Town
a city ruled by a top - ranking demon exiled from its home. The demon has ambitious plans to create a new demilayer here, but for now is building an army to threaten and raid the surrounding scrps of civilizations nearby. The locals do not trust anyone, but will trade peacefully with most others. They are interested in poisons, powerful weapons, or anything else that could bring victory, and will kidnap and sell their own children to obtain something really powerful.
 Alternate Variances