Adding to the Lower Planes

[D&D_Fan]

This thread is for the purpose of adding new sub-realms to the planes of D&D (and also Pathfinder I guess) And these new realms can totally come equipped with new rulers and new monsters, and even lore tidbits. The goal is not to change upthe lore too much, but if a new lore is developed, that's all right.

Rules Suggestions:

• New layers of Hell should typically be presented as 'lost layers' which still exist but were either taken by the forces of the Abyss, adrift in the sea of planes, or otherwise hidden or secret. This is only to not create too major a divergence in lore.
• Additional layers of the Abyss... Just go wild. There are allgedly infinite layers.
• Additional Carceri layers would be ones lost miles beneath the ice of Agathys.
• More layers for Gehennom would probably look a lot like Krangath, but if you have a new idea, go ahead.
• Acheron has 'layers', but they are all made of floating objects that drift around a bump into each other.
• Pandemonium also has layers. I don't think many people are big Pandemonium fans though.
• Abaddon is Pathfinder, and it also probably doesn't have vertical layers. It has sub-regions though.

Honestly, this is all suggestions, go wild with stuff.

I'll post some example new layers later today.

[D&D_Fan]

Burbuil - Acheron
This layer is composed of bubbles of water of varying size. Many of these bubbles are filled with armies of Koalinth and Sahuagin. Others are filled with sea serpents, krakens, and evil dragon turtles. When these bubbles collide, they merge, creating one massive battlefield. To non-aquatic beings, this realm is quite disorienting, due to having no real direction of gravity, but some still build warships and sail them on the surface of the bubbles.

Fulvirg - Acheron
This layer is composed of floating cylinders made of copper and great storms of lightning. As the energy cascades across the field of copper, some creatures ride the currents to reach new rods. It's a highly dangerous layer, and many adventurers are likely to find themselves fried like an egg in such a realm. And cylinders have weird gravity too. Most people don't bother with this layer at all.

Gannethys - Carceri
The final prison of many Elder Evils, at a least portions of many Elder Evils, such as Pandorym and Tharizdun. Their essences are split among orbs of cold, indestructible metal or crystal. Each orb is so far apart from one another that each from each one, no other can be seen. It is at all times devoid of all beings except for a single unique demodand. These beings may not be allowed to be freed. And yet, shattered orb fragments drift in the black void of this plane as evidence: They cannot be held forever.

Gulia - Hell
This realm is another icy, damp hell, much like Cania or Stygia. Those who travel through it will become hungry much quicker than they ordinarily would. But there is no sustenance to be found. At the center, a great gaping whirlpool draws in the condemned souls, infinitely spiraling down. Monstrous three-headed hellworms were the native beast. It may have become the layer of the abyss known as Sholo-Tovoth.

Laspys - Carceri
The worlds of Laspys are blobs of dreadful mud and tar from which there is no escape. Only universal solvent could hope to free someone caught in the embrace of this dreadful muck. Even the rain is just tar and boiling oil. It is quite unpleasant for most. Demodands love this place. It may, in fact, be their native layer, that they were shaped from the primordial sludge into their demodandic selves by Apomps.

Libidine - Hell
This location of this layer is unknown. This realm is one of howling darkness, with the occasional flash of lightning. It's a very empty place, spiraling adamantine towers, perhaps fortresses, stand, buffered by the constant wind. It is a layer devoid of life. Some scholars speculate that this was the layer that Graz'zt once ruled over before he defected to the evil of the Abyss. It has since been sequestered away so that he might never reclaim it. Those who discover the few remaining routes to this lost layer may find lost treasures of immense power, but should Graz'zt ever discovered his lost layer, it might mean a great upset in the Blood War.

Nasilus - Hell
A great forest, violent and bestial, run through by rivers of boiling blood. Ferocious fiends were once found in these woods. And they still might yet. Some scholars speculate this layer was split into several layers of the Abyss, including those of Yeenoghu, Baphomet, and several other lords.

Ull-Shalath - Gehennom
A great fortress layer of Gehennom. Rather than having 45 degree slopes, these slopes are so steep as to be 90 degrees. The fortresses of this layer inaccessible to most non-yugoloths simply due to the difficulty of reaching them. Great decisions of the Blood War on the Yugoloth side are often made in these odd, spiky horizontal citadels. They can also serve as vast barracks for vast contingents of Yugoloths. Were the plane to collide with any other. These spiky sideways towers would impale the other plane, allowing a quick invasion. Barring that, they lie mostly empty.

[D&D_Fan]

Bridge, The - Abyss
An empty layer made of red earth. A bridge made of abyssal metal juts out over the edge of the layer above a void. This bridge is perhaps millions of miles long or not even measurable at all. It has fallen into disrepair. It was a joint venture by several unknown demon lords, meant to lead to Hell, but it was abandoned near the end of construction. Demon Lords don't work together well.

Crush - Abyss
This layer has a magical force of gravity so much stronger than that of the Material Plane that all travelers to it are instantaneously crushed flat. It has no lord for a good reason. It has the same gravity of an earth-sized planet made entirely of Pelleum. An average person on that layer's surface would experience 3,275,227,710,000,000,000 J of gravitational force.

Invergal - Abyss
Fundamentally, large creatures are small, and small creatures are large. Players may have some trouble fighting demonic bacterium the size of dragons, and most giant demons hate the layer. The lord of this layer is Gastroenterax, the Infectious, a lord that happens to only be a few microns tall in any other layer. It's otherwise full of medieval castles made of tiny boulders and giant algae-like plants instead of trees.

Lonesome Layer, The - Abyss
This layer can only be inhabited by a single being at once. Once that slot has been filled, it is inaccessible and all other travelers are locked out or forced out, but objects can be sent to the plane. The realm itself is a vast castle filled with unimaginable treasure. The lord is Amlotraz, a minor demon lord. He is content to stay in his perfect kingdom forever, ignoring any request by any other lord to leave. A very healthy and well adjusted individual.

[brian 333]

Flesh
The ground is living skin, layered over live flesh. Grass and forest do not exist. Instead hair grows to impressive lengths. Pools of sweat and blood can be found or created. The living things on this plane are demonic fleas, ticks, and other parasites.

As beings consume the flesh to survive, they replace their living body with bits of planar material so slowly that eons later they are no longer themselves, but part of the plane. These malformed parasites dig into the flesh and become trapped in a parasitic cyst which leeches what remains of the being. When the being's essence has been absorbed the cyst erupts in a putrid fountain of puss.

No demon lords live here, being all too aware of the cost of doing so. One may visit from time to time. Lesser demons who do come to the plane quickly morph into parasite forms, and begin the transformation into Flesh.

[the_david]

Flesh
The ground is living skin, layered over live flesh. Grass and forest do not exist. Instead hair grows to impressive lengths. Pools of sweat and blood can be found or created. The living things on this plane are demonic fleas, ticks, and other parasites.

As beings consume the flesh to survive, they replace their living body with bits of planar material so slowly that eons later they are no longer themselves, but part of the plane. These malformed parasites dig into the flesh and become trapped in a parasitic cyst which leeches what remains of the being. When the being's essence has been absorbed the cyst erupts in a putrid fountain of puss.

No demon lords live here, being all too aware of the cost of doing so. One may visit from time to time. Lesser demons who do come to the plane quickly morph into parasite forms, and begin the transformation into Flesh.

Like Occipitus, the 507th layer of the Abyss? Or more like Occipitus on steroids. I like it.

[Millstone85]

Deep End, The - Abyss
This layer is a Far Realm incursion into the Abyss, though some legends depict the whole of the Abyss as a whirlpool that formed around this tear in reality. A variety of landscapes can be found in the Deep End, with the peculiarity that any landscape will appear superposed with transparent intangible visions of other landscapes. At the cost of its entire turn, a creature can will itself from its current position to the corresponding position on any other landscape it can see.

The Deep End is often visited by gods with ties to both the Demon Lords and the Great Old Ones. For example, Ghaunadaur, a deity shared between aboleths, oozes and dark elves, mainly resides in the Demonweb Pits of the goddess and demon lord Lolth, but goes to the Deep End to commune with a Far Realm entity called the Amoebic Sea.

Outside of such divine connections, the Deep End is considered a battlefield between demons and aberrations. Some sages see in this a second Blood War which, like the one fought between devils and demons, must never be won by either side lest all of reality fall to the victor.

[D&D_Fan]

Stone - The Abyss
This realm causes every being that enters it to be automatically affected by a planar aura of petrification; All that travel to the plane are instantly frozen to stone. The only animate inhabitants are evil elementals of stone (such as gargoyles), animated statues, golems, and other constructed and elemental beings. This layer has no lord.

The Great Trudge - Abyss
This plane of red skies and black earth is inhabited by a heard of massive and ancient demonic beasts that tower thousands of feet into the sky. Titanic creatures, with long pale legs that vastly dwarf redwood trees in size, and weeping humanoid heads, their minds idiotic, animalistic. Ancient Cities and fortresses stand on the backs of these foul beasts of burden, left barren and vacant. They trudge in a infinite circle, waiting to be used for whatever endeavor their masters might intend. But their masters are gone, and they are abandoned. Few people know of this layer. It's mostly empty. If the demon princes learned of it, they might seek to use these beasts in the blood war or against each other.

Great Trudge Creatures are something like Macro-Medium sized, so very very big.

[D&D_Fan]

The Dark Dreaming
Sometimes, the minds of dreaming abberations, aboleth, illithid, beholder, kuo-toa, all may have their minds drawn to a dark and unknown place in a point in their lives, of impossible spires and infinite flat plains, in which their darkest thoughts are made manifest into cruel and unusual loumara demons, more warped than the dreams of the gods will ever generate.

Geographically, the sky is stark white without definition and the ground is black with conic spires reaching into the sky.

The demons from this realm are spectral and ephemeral, but nightmarish, with rubbery writhing shapes and structures, misshapen and unwelcome animal parts, and maddened tyrannical desires. The minds of the aberrant are themselves, aberrant.

TLDR: An ancient realm draws the dreams of aberrations here to make new and awful demons.

[brian 333]

Forlorn

The sky is yellow with occasional clumps of orange clouds. Eternal twilight never darkens to night, nor does it ever brighten to day. The ground is brown or brownish red clay covered in a fine layer of yellow dust which at times is picked up by the winds and blown around, obscuring vision. Most of the time the winds are calm, and one can see to incredible distances across the flat, featureless expanse. There is no water of any kind here; it never rains.

The nature of this plane is that any two things separate. They do not move, but distance between them increases at the rate of 10'/round. There is no sensation of movement, nor any discernable creation of new ground. To the observer it simply appears that the other is becoming more distant.
Given the infinite nature of the plane, this expansion appears to be continuous and happening everywhere on the plane at once.

There are no natives of this plane. Its nature causes even the most hardy individualist to wither and eventually die of loneliness. Those who die this way crumble into yellow dust to be blown about on the winds.

There is a (sort of) Lord in this realm: a being of elemental loneliness. It has been here since the Abbyss formed, jailed by the demon princes as they fought among themselves for control of the planes. So long abandoned, the being no longer remembers it ever had a name, nor that it ever had an existence outside of its prison. However, it has always been, and continues to be, a major contributor to the prime powers of The Abbyss.
Its nature of constant expansion is leeched off by the greater demons, and channeled to make their planes expand. This same power is what causes the spontaneous creation of new planes as well. However, in a few trillion years or so the energy required to power this continuous expansion will begin to be siphoned from the other Abyssal planes, then from adjacent planes, and eventually from the entire multiverse, turning all of reality into what is now known as Forlorn.

[Millstone85]

Lityerses - Acheron

From a distance, the floating blocks of this layer look as if made of metal foam. These used to be cubes, gears and other large structures found through Acheron and its neighboring planes of Law, until they were drawn into this layer to be hollowed out by countless mandibles. For indeed, Lityerses is a battlefield between two massive swarms of insect-like metal eaters.

Clockwork horrors are constructs with a single driving goal: to build ever more of themselves. They are also highly communicative and methodical, turning the blocks into resilient latticeworks that house numerous planar portals. Special clockwork horrors, recognizable by their gold plating, supervise each block and ensure the unity of the swarm through all of Lityerses.

Rust monsters are beasts with the ability to find nourishment in metals after magically corroding them. Devoid of language and only somewhat attentive to each other, rust monsters tunnel in a haphazard manner that causes blocks to break apart on collision. However, by some blessing of Lityerses, any rust monster unearthed from the debris will instantly return to life.

If given the choice, the clockwork horrors would evacuate the layer and let the rust monsters starve to death. Yet whenever the horrors manage to leave Lityerses for another layer of Acheron, or more rarely for the planes of Mechanus and Baator, they eventually find themselves back along with any new territory they took, and often about to collide with a rusty block.

Other creatures can end up on the layer. The place is particularly cruel to Acheron petitioners that clockwork horrors and rust monsters will register as food, such as autognomes, warforged and metallic dragonborn. The unfortunate souls will keep resurrecting on Lityerses to be taken apart again. In constrast, individuals bearing no metal might be ignored by both swarms.

[D&D_Fan]

Acheron Oddities

An ancient mummy warlord who has constructed a large pyramid of black iron with which they skirmish with other Acheronian factions. They seek to make a mummy army and become a major player. This has not happened yet. - Avalas

An atypical cube that is covered in strange tubes and glowing lights, and is inhabited by pale humanoid beings similarly adorned in tubes and lights who speak of "assimilation" but are generally just confusing to the other factions present on the plane. - Avalas

Many stranded spelljamming ships, protected from becoming petrified by their spelljamming magic, but stranded nonetheless. Some send out distress calls, some abandon ship, some starve, some get eaten. - Thuldanin

A great rhombicosidodecahedron that is worshiped as the shape with the most edges in Acheron with planar pilgrims traveling to find it and pay homage, and to prevent it from colliding with other shapes as it travels its divine course. It may yet be an actual elder being, albeit probably not a good one. A rival cult exists which worships a snub icosidodecahedron, which does have more sides, but they don't have as many edges or vertices. - Tintibulus

[brian 333]

Apostate

All of the gods know of this plane because it is where they send, from time to time, the souls of those who falsely profess to be clerics of their faith. Beings of any alignment may be sent here, but seldom do Good aligned souls end up in this demi-plane of Gehenna.

A new soul arriving here will be dumped before the podium of Gadrix, a mortal punished for deceiving millions of followers. In life he would hold ceremonies in which he would judge those placed before him for their worthiness. In death he is condemned to stand within a suit created by pouring all of the gold he acquired for himself through donations to his false church. Only his mouth can be seen under the molten suit of gold, and he pronounces all who come before him unworthy.

The guilty must climb up the slope to the top of the mountain where, they are told, a doorway exists which will send them on to their permanent afterlife. Along the way they must collect the wealth they took under false pretense in life. Whenever a soul slips or falls the strange gravity of Gehenna drags it down and the soul must begin again from the bottom, first collecting the scattered coins before proceeding higher.

For particularly heinous crimes, Gadrix may decree additional punishments, such as having the soul dipped in molten gold, having devils inflict all the punishments their false faith decreed would be the fate of those who refused to follow them, or binding them with long chains and having them wrap and whip them when they fall.

Climbing for days, weeks, and months through waterfalls of molten metals, across obsidian shards, and up slick glass slopes only to slip and fall then being forced to try again by bone devils and other denizens of the infinite mountain is made worse by the clouds of acidic, sulphurous fumes, geyser blasts, and lava.

The few who do reach the top are allowed to walk into the caldera of the volcano, where in the center of the lava lake, on an obsidian island, stands the doorway to their afterlife. Some spend many thousands of years climbing to get out, only to be sent somewhere infinitely worse.

[Millstone85]

Just quoting my favorite layers of yours, so far:

Burbuil - Acheron
This layer is composed of bubbles of water of varying size. Many of these bubbles are filled with armies of Koalinth and Sahuagin. Others are filled with sea serpents, krakens, and evil dragon turtles. When these bubbles collide, they merge, creating one massive battlefield. To non-aquatic beings, this realm is quite disorienting, due to having no real direction of gravity, but some still build warships and sail them on the surface of the bubbles.

Forlorn - Abyss
The nature of this plane is that any two things separate. They do not move, but distance between them increases at the rate of 10'/round. There is no sensation of movement, nor any discernable creation of new ground. To the observer it simply appears that the other is becoming more distant. Given the infinite nature of the plane, this expansion appears to be continuous and happening everywhere on the plane at once.

[Bohandas]

Does anyone perchance have a saved copy of the old abyssal layers thread from the old WotC forum?

[brian 333]

Hunger

Deep in the depths of The Abyss is the plane of Hunger. Emaciated, shriveled, ghoul-like demons prowl the landscape in constant search of food.

The land itself is heaps of filth left behind by countless ages of demons. Within this filth demons hide from stronger and seek weaker demons to consume to satiate the maddening hunger this plane imposes on all who dwell there.

Cannibalism is the norm here, and those CE souls who were criminal cannibals, (as opposed to those who did it as a desperate attempt to survive,) are deposited in this plane. A mane formed in this layer must eat or be eaten. Those who succeed may level up through various demonic forms, but at every metamorphosis they become ever hungrier, requiring ever increasing amounts of food. A demon on the Plane of Hunger must eat 1hd every 100/HD hours or it will starve. It temporarily loses 1HD every 100/HD hours that it has not eaten, and can only regain the lost hd by consuming demons. Each hd consumed restores one lost HD until back to maximum for that demon type, at which point the demon may begin leveling up again.

Of course, higher level demons seek out starving demons to eat because they are weaker but their permanent hd count for their experience value. A demon which has been eaten is eventually shat out as a cyst, which hatches as a 1hd demonic grub which eats it's way through the mounds of filth until chance allows it to consume at least 1hd of demonic flesh. At that point it metamorphs into a mane. These grubs are the usual fare of manes, (and other starving demons,) which dig through the filth hunting them. A grub may be consumed multiple times, only to encyst and hatch again.

Adventurers who find themselves here are trapped; normal means of planar travel do not work. There are two ways out, and both require assistance from outside. A demon prince may summon beings from this plane, typically for the purpose of enslaving them or otherwise making use of them, and a spellcaster may open a Gate from outside the plane. Such a portal will immediately attract the attention of every hunger-crazed demon in the area smart enough to recognize it as a way out.

[D&D_Fan]

Abyss Layers Past 1001
These layers become increasingly chaotic or increasingly evil, but they do become weirder and weirder.

Perfection - 1002
An ancient celestial citadel with gleaming towers, bountiful food, beautiful gardens, and other assorted good things and good thing byproducts. A mile from the citadel is a perpetual free-for-all battlefield, as demons of greed and envy tear each other apart to claim the citadel, the layer creating more demons to replace those that fall.
The lord of the layer is a fallen angel, originally a deva, not a tremendously powerful angel, but one who took control of the plane, and warped it. His citadel is an object of desire to fiends, it twists them. He relishes in watching them fight each other, they will never take the citadel because they could never share it. All they ever do is infight.

Claustrous - 1003
A small, empty, cylinder-shaped layer. It is 10 feet in radius, and 20 feet in height. It is much to small to do anything in, and it has no lord to lord over it. The walls and floor are grey stone.

The Mineshaft - 1004
This is a large, perhaps infinite system of caverns, perhaps reaching into the plane of earth. Within it lie veins of a rare and powerful metal, near-indestructible, able to shatter steel and adamantium alike. The metal emits a deadly effect however, and prolonged exposure will lead to diseases that cannot be conventionally healed. Demons don't care though. They just mine the stuff and use it, they don't worry about such pesky things as "cancer" and "radiation poisoning"
This layer is owned, but by who? And where does this mined metal go? Someone is taking it for something. None of the other lords of the abyss have been able to reach it with their servants.

Gearsclang - 1005
Like an off-version of Mechanus, this is one of the layers that powers they abyss (there are others, because there's no straight paths but there are many truths), makes it coherent, able to generate new things. But it's constantly breaking. Gears and chains and springs hardly work right in a plane of chaos, they clang and screech and snap and click. The sound alone will drive anyone mad. Black tar pours from exposed pipes, scalding steam burns flesh. But hey, it's a job that must be done. No lord owns this layer, but there are many demons who maintain the gears behind the abyss. It's a great chaos machine.

[Bohandas]

Land of the Furious Sun - Abyss
Abyssal layer 775 is a the inner surface of an enormous sphere of craggy rock. At the center of the sphere lives Leagaten, an angry sentient red dwarf star. Leagaten is perpetually angry and constantly shouts invectives. The din of his swearing is audible throughout the layer.

Leagaten smites inhabitants of the layer who draw his ire,, (which is largely the same as drawing his attention), with gouts of flame shot from his body, which hit the ground one round later with the effect of a level 20 flamestrike spell. He can also attack any being on the surface of the layer with searing light. As a result of this happening frequently, much of the landscape is barren and scorched with very little plant life, although some plants do grow, as the surface of the layer is extremely vast and Legaten can't attack everyone and everywhere at once. Even though he cannot directly attack more than a tiny portion of the surface at once, he is inappropriately close to that surface (seperated from it by only one or two times his diameter) so the layer is therefore dangerously hot and dazzlingly bright. Most of the little plant life that does grow is of a sort resistent to dehydration and whose lifecycle includes being occasionally burned down.

The layer is a popular meeting spot and mustering ground for conspirators against darkness and/or undeath themed demons and abyssal lords, as well as a popular hiding spot for those on the run from darkness depending beings. The proximity of the sun and eternal day put their night-dependent enemies at extreme disadvantage.

The layer is self-contained. Digging down more than a mile or so brings one back out onto the surface under(?) the opposite side of the sun.


Chiralia - Abyss
Chiralia is a finite and self-contained layer of the abyss which takes the form of an enormous hall of mirrors. The curved funhouse-style mirrors gradually, yet painfully, warp the creatures reflected in them to match their distorted reflections; visitors who linger too long in front of the same mirror are eventually killed by being twisted into shapes that cannot support life.

The layer itself is twisted up as well, into a non-orientable surface equivalent to a projective plane or steiner's roman surface. In layman's terms this means that the boundries of the layer are joined to themselves as in the diagram below; A to A, B to B, 1 to 1, 2 to 2, 3 to 3, etc. (the + signs are just empty space/the landscape of the layer, and the Xs are just placeholders)

X123456X
A++++++F
B++++++E
C++++++D
D++++++C
E++++++B
F++++++A
X654321X

Traveling the entire distance of the layer once mirror reverses a creature or object, which - for material creatures (but not the native demons) - may make non-mirror-reversed food indigestible. Traversing the length of the layer again undoes the mirror reversal

In addition to all this, many mirrors are portals to other mirrors and/or are mirrors of opposition. In the case of ones that are both, the double appears on the opposite side of the portal

The Exploded Clock - Abyss
Abyssal layer 15383224, made from gears ripped out of Mechanus in anger by Orcus while he possessed the previous Primus during his search for his wand. These gears were scattered throughout the great wheel and those that landed in the Abyss became the Exploded Clock

This layer is self contained (it wraps around) and the gears still whiz around it with their original velocity, occasionally colliding and crushing anything unlucky enough to get caught in the collision. The gears never lose velocity after these collisions but frequently throw off sparks as well as shrapnel that flies off into the void creating additional hazards. Additionally, random gigantic (though on a smaller scale than the gears) clock pieces have begun appearing in the layer, including springs with razor sharp ends, heavy double-ended pendulum arms, massive bells, spear-like clock hands, broken glass, and razors in the shape of the numbers 1-12. These new pieces all share the enormous velocity of the original gears. The layer is home to a variety of bird-like demons as well as undead formians and modrons.

Forest of weapon trees - Abyss
On the 896th layer of the abyss there is an endless forest where all sorts of weapons grow on trees and vines. Mostly edged/piercing weapons that sprout new weapon trees when left in the corpses of their victims, but there are also blunt weapons and even grenade fruits that explode when thrown, dispersing their seeds.

The Sandstorm Plains - Abyss
The 7152nd layer of the Abyss is a vast desert. While there are no normal precipitation in the layer it does constantly rain sand. The surface gradually gets higher and higher as more sand rains down (it comes from nowhere) and any stationary structures are covered over in a matter of weeks, if not sooner, unless they are constantly dug out (and even then the structure ends up in the middle of a treacherous pit whose sides could easily collapse and bury it)

Dystopialis -Ravenloft
This island of terror is a dysfunctional democracy characterized by a bitter split between two rival political parties, both of whom are awful. The Fruits of Industry Party essentially wants the populace to live as the abused servants to the party's elite. The Neverending Bliss Party' platform on the other hand involves forcibly euthanizing anybody who seems unhappy or unfriendly. In truth it doesn't really matter who wins, as unbeknownst to everyone both parties are run by the domain's darklord, who has a split personality and shaoeshifting abilitkes

The Sound Plains - Abyss
Abyssal layer 3425 is pervaded with music coming from nowhere which frequently abruptly changes, just when a song starts to get good. In addition to being really annoying, this also imposes a penalty to listen checks and acts as a forced countersong (at +0) against any sonic or language dependent buff anyone attempts to cast or otherwise initiate

[D&D_Fan]

Deathtrap - Abyss
Those who awake in this layer find themselves in a vast dungeon filled with brutal contraptions. Tormented by a sadistic demon lord. They may find themselves with a bear trap rigged to their spine, blinded by spikes, having their hands crushed by a falling portcullis, or disfigured by acidic spray, or electrocuted or dismembered or any other sort of damage. The only way out is through bargaining with or entertaining the demon lord, an anonymous figure who never leaves their chambers, and has not been seen on any other layer.

The Corpse Pile - Abyss
A place where the bodies of demons slain in such a way that prevents their essence from being dissolved back into the abyss are disposed of. It's just a layer of dirt dotted with piles of demon corpses. It's rare that a demon is slain in a manner that leaves a body but that the body can't be reabsorbed by the abyss. Perhaps a slaadpole gets inside the demon, or it gets flooded with positive energy. For whatever reason, it's easier for the abyss to leave the body here.

Hotel Abyss
A giant hotel like layer full of creepy hotel related things, ostensibly for guests of the abyss. Demons hate working in it. What few know is that once you check in, you don't check out so easily. Players may find all sorts of guests here. Vampire lords, devils, yugoloths, celestials, wizards, sorcerers, modrons. Getting the keys to get out is an adventure in and of itself.

[Bohandas]

The Forum - Abyss
Abyssal layer 41315 is a massive fractally repeating Roman forum, with other types of town squares occasionally sprinkled in, serves as an assembly place for political discourse in the form of bloody violence comitted with the many weapons convemiently strewn about

The Bowels of the Underworld - Abyss
(this one's actually based on a location from the computer game Afterlife)

This abyssal layer, layer 1777, is alive, specifically it appears to be the intestinal tract of some kind of enormous beast. In terms of inhabitants it boasts more human centipedes per square mile than any other location in the multiverse.

Planets At War - Abyss
Abyssal layer 7716 is a solar system consisting of a black hole orbited by a small star and several dozen planets and dwarf planets. The planets are all at war with each other, literally. The planets are sentient and don't get along, and every so often one of them will try to ram one of the others into the sun or the black hole. This naturally has devestating repurcussions for both planets' inhabitants, regardless of whether it succeeds or not. New planets occasionally pop up in various ways, and so the solar system never runs out. Planets will sometimes divide by binary fission, or a new one will be spat out by the sun, sometimes one will spontaneously spin up out of space dust and debris, and sometimes a pair of twin planets will simply pop into existence out of the void; this last kind almost always immediately smash each other into dust unless one of them is sucked into the black hole or destroyed by something else first. Sun occasionally disgorges huge or even gargantuan Callers in Darkness (expanded psionics handbook), often with fire or evil related templates. The black hole even more rarely disgorges Callers in Darkness that can be up to collassal+ in size and often have multiple templates.

And the spelljamming inhabitants of the planets are also all at war with each other.

Several facilities exist in orbit around the black hole dedicated to launching interplanetary projectiles out of the black hole via the Reverse Gravity spell (from Planar Handbook)

[brian 333]

The Hunt:

This Abyssal demi-plane was created by a demon-lord for his amusement. Unfortunately, it amused him to death.
On a character's entry to the plane, a demon forms with virtually equal power to the entrant. This demon is then driven to hunt the being in whose image it was created. There is a telepathic bond between the creation and its target which allows communication if both parties are willing. Both parties also are able to determine, by concentrating for a round, if the other is near or far, (but not exact distance, movement, or direction.) This bond cannot be used to cause harm, nor can it convey magical compulsions or other effects.
The demon is typically created with the features the entrant most dislikes in himself. A person self-consciois about his premature balding, for example, may meet an extremely hirsute creature with a completely bald head. Each demon in this plane is specific to the creature it was created to hunt.
The only demons in the demi-plane are those who defeated their nemesis or those still hunting. They can be slain, but if slain by someone other than their target they dissolve and reform elsewhere to resume their hunt. The only way to permanently destroy one is for its target to kill it.

The plane is huge, but not infinite. It has a surface of about three Earths, and has just about every terrain one could imagine, from arid lava fields to dense jungle, bleak deserts to unfathomable oceans, mountains that rise out of the atmosphere and deep caverns that penetrate the core of the plane.

The lord of this realm calls itself, "Great Prince Thgie Eht Yrneh, Master Of The Hunt, Lord of the Domain of Fang and Claw." (Apparently, its creator hated the titles bestowed on it.) Weak for a demon prince, it was strong enough to defeat its target and now its existence is linked to the plane's. If either are destroyed in a permanent way, both will be.

The many demons here enjoy kill-stealing, so they will not hesitate to attack anything that looks weak enough to kill. The rule of this plane is 'Hunt or be hunted.' The reality is more like, 'You are being hunted.'

[Bohandas]

Phonanomava - Abyss

This abyssal layer punishes anybody who makes an imperative statement (ie. "do this" "don;t do that" etc.) or who states any sort of rule or commandment (ie. "you may do this" "you may not do that" etc). The words reverberate inside the mouth of the speaker, dealing sonic damage and possibly blowing their jaw off. Something similar also happens if such a statement is attempted via writing or gestures; the offending limb is wrenched into an unnatural position and potentially crushed, broken, dislocated, or even torn off. And so it goes with all other forms of communication, even telepathy (with which seizures, psionic damage, and insanity may result). Occasionally other disasters may befall a speaker instead, such as curses, being struk by lightning, being dominated or geased to do the thing they said to do themself, or even being disintegrated.

There is also a much rarer related phenomenon wherein the use of any sort of circumlocution may occasionally cause space to rapidly expand, leaving the speaker surrounded by miles of empty desolation

[Bohandas]

Fecaurum - Abyss
This abyssal layer appears to be full of rare treasures, but these treasures are in fact partially real illusions (although unlike most partly real illusions they are not based on shadow). When removed from the layer these treasures revert to their physical substrate, which is literal bull****. In the case of magic items, they also turn to bull**** if their charges run out (which may happen randomly to an item that should still have charges left or even to one that should never run out of charges). The illusions are very convincing and only someone extremely strong willed and wise could possibly see through them while on the layer.

Murder-Con
A seemingly infinite convention center holds a seemingly endless convention dedicated to the art of murder and warfare. The convention center exists simultaneously on Gehenna, Pandemonium, and the Abyss

The Umbrella - Far Realm (or possibly Faerie?)
A small chamber where an umbrella is embedded in a mound of wax. Acid congeals on the umbrella and drips up into the sky. The umbrella is semi-intelligent and insults anyone who comes near

Pilabum City - Ravenloft
A city banished to the mists for its use and abuse of blood magic. The city had ubiquitous magic in every household, but it was powered by the mass slaughter of intelligent magical beasts, whose blood was pumped out into households and shops to recharge the magic items there. The power plant did not make it to the mists, and now the residents are eager to waylay outsiders and take their blood. The darklord is the inventor and popularizer of this system of blood magic, a powerful mystic theurge. This particular mystic theurge worships a dying-and-reviving vampire god whose renewed undeath brings the winter.

[ahyangyi]

Chiralia - Abyss
Chiralia is a finite and self-contained layer of the abyss which takes the form of an enormous hall of mirrors. The curved funhouse-style mirrors gradually, yet painfully, warp the creatures reflected in them to match their distorted reflections; visitors who linger too long in front of the same mirror are eventually killed by being twisted into shapes that cannot support life.

The layer itself is twisted up as well, into a non-orientable surface equivalent to a projective plane or steiner's roman surface. In layman's terms this means that the boundries of the layer are joined to themselves as in the diagram below; A to A, B to B, 1 to 1, 2 to 2, 3 to 3, etc. (the + signs are just empty space/the landscape of the layer, and the Xs are just placeholders)

X123456X
A++++++F
B++++++E
C++++++D
D++++++C
E++++++B
F++++++A
X654321X

Traveling the entire distance of the layer once mirror reverses a creature or object, which - for material creatures (but not the native demons) - may make non-mirror-reversed food indigestible. Traversing the length of the layer again undoes the mirror reversal

In addition to all this, many mirrors are portals to other mirrors and/or are mirrors of opposition. In the case of ones that are both, the double appears on the opposite side of the portal

Ah, this is the abyss layer we talk about every time someone asks "perhaps we can have a torus-shaped layer". The classification theorem of closed surfaces is the truly (un)holy guide of the infinitely many layers of the Abyss!

[Starlit Dragon]

The Reflecting-Plane
(Layer of the Abyss)
A dark mirror of Limbo, this layer warps and reflects the thoughts of anyone inside it. Think about anything for too long, and a violent facimile of it will form. Think of a lost lover, and you might see his silhouette in the distance, slowly coming closer. But it is not him. It has too many hands and too many fingers, its eyes are not set right, clothing melded to its flesh. The thing that is not your lover will approach, and its wrongness grows more evident as it becomes more real. It will charge at you, making meaningless noises in a voice that is almost his, and it will try to hurt you, with hands or teeth or whatever weapons your imaginings gave it.
If your thoughts drift, the things that emerge from it will be stranger, more formless or melded together. And if there are more people with you, which their often are, as this plane is inhabited by fiends and prisoners, their own thoughts will shape the world, building off themselves and each other.

There is a demon lord, and his own dreams form the basic landscape of the plane. Anyone who searches for them, however, will find the products of their own imagining in the search, which would make finding them nigh impossible.

[D&D_Fan]

The Tower - Abyssal Layer #780

A nearly empty layer that contains only a massive tower bridging the layer above it and below. There is no ground on which to stand on, just an adamant tower reaching out of and into clouds of black mist. Inside the tower is a spiral staircase, thousands of stories tall. Periodically, every hundred stories, the tower opens up to a balcony, from which to view the emptiness of the layer. Those who spend more time within the tower are slowly eaten away at by the emptiness and monotony around them, consumed by an oppressive, suicidal depression.

The lord of the layer is often theorized to be the Black Mist itself. A malevolent watcher, waiting for the next victim of the tower to throw themselves off the tower and into its dark maw. And The Black Mist seldom goes hungry.

[Bohandas]

Fantasy Borg Cube - Acheron

This cube is swarming with spawn creating zombies all under the command of a power hungry necromancer whose living head has been grafted onto an undead body. The necromancer can freely command any of the zombies on the cube and is aware of anything that they are aware of


Armageddon- Gehenna

The secret layer of Gehenna, currently accessible only via a portal in the Crawling City. A stronghold and arsenal of the General of Gehenna, where many artifacts and monsters more powerful than what the sellsword general commonly rents out are holed away in case fortune ever turns against him

[brian 333]

Gelid
This sub-dimension is a demiplane off of the Nine Hells. It is so cold that its single, plane-encompassing ocean is frozen. Only a few of the greatest devils know of its existence, and only the Dukes are aware of the true purpose of this place.

Any visitor has Con days before becoming frozen. Creatures with DR versus cold are allowed a daily save vs Fort, with DR minus 5 then divided by 5 applied as a bonus to the roll. Otherwise, the creature's Con is temporarily reduced by 1 each day until, at 0, the creature becomes frozen solid. Even outsiders and creatures with cold immunity are in danger.

Once frozen the creature is stuck to the ground, and sinks 1" per year forever, going deeper and deeper into the unfathomable depths. Unfortunately, the victim is still aware. Day by day, for eternity, such unfortunate beings, unable to move as ice burns every atom of their body.

Ice demons roam the surface, but become mired in the ice. One may suppose there is some entity sending more. They ignore anyone, for the most part, unless they try to free a victim, at which point they attack. They may also offer contracts to victims, proming to release them in exchange for their freedom. They have no power to grant freedom, but are very clever at wording contracts which can be fulfilled without liberating the victims.

Some greater devils can send victims here via gates or other magic. The Dukes can summon frozen beings en-masse or individually if their names are known. These frozen beings are ice-wights when summoned in masse, an army of evil creatures which can inflict cold damage with a touch, and death at their hands causes the being to spend its afterlife in the ice of Gelid.

[D&D_Fan]

Solitum - Hell - (Defunct)
This layer is flat with a large semi-sphere hollowed out from it, and all on the sides of the semi-sphere are holes. The layer looks like a massive sieve, almost, except that the holes don't lead out. Each hole leads to a small cave, and each cave is a private torture chamber for an individual who has angered hell directly. The holes are one-way, at least to those who cannot fly. Some of them are full of flames, some are wet and dark, some are sharp, some are tight, all are nasty.

The layer was owned by an archdevil by the name of Azzagorax, who was generally very hands-off when it came to running things, preferring to let his underlings do the work and call the shots.

But the layer turned out to be a resource sink and was abandoned. Azzagorax was demoted back down to Pit Fiend and he was fine with that. Honestly, he never liked being an archdevil.

Nictor - Hell - Other
This layer, if it can be called that, is shaped like a monstrously huge insect nest, hexagonal, papery, rough, squishy, etc... And that's what it is exactly: a Hellwast nest. In terms of location it floats some distance off to the side of Baator, but it can still be reached and it exists in the same 'hellspace'. It's perhaps one of the few layers that doesn't answer to Asmodeus at all. The archdevil of this layer is an entity known as the Hellwasp Queen, her real name being unknown since she's a wasp and doesn't talk to anyone but wasps hardly ever. The hellwasps fly into the rest of hell every day, same time every time, and they just take. They take devils, angels, and mortals alike, and the pack them into the walls, either to extract their nectar and turn them into hellhoney, or to petrify them into more walls, expanding the nest further.

[Bohandas]

Progeria -Hades? Abyss? Ravenloft?????
Creatures in this region age at twice their normal rate, must eat and drink twice as often, and must even breathe more quickly. The breathing aspect has the effect that all creatures that breathe become winded after far less exertion than usual (with the exception of creatures like whales that are already accoustomed to doing lots of stuff while holding their breath for extended periods; although even these can only hold their breath for half as long). To make matters worse, creatures entering the region without magical protection instantly "catch up" and double their age (in the case of people leaving and reentering, only time that has not already been doubled is doubled when they reenter, usually this will be limited to the time after they left, but may be more if they somehow avoided "catching up" the first time they entered). Age related penalties accrue but age related bonuses do not, and a creature that ages up enough may die

The Bottomless Pit Hell/Abyss
A transitive demiplane which theoretically links the Grand Abyss with Nessus. It is not traversable by conventional means however because its length in that direction is infinite. Technically an extension of the Grand Abyss. Another failed attempt to breach Hell directly, similar to The Bridge, above.

[D&D_Fan]

Rubigo (City) - Dis, 2nd Layer of Hell
Banished from the city of Dis, but not from the layer of Dis, devils and the damned alike live in abject squalor and filth in the slums and camps set up around the great city. Like a great city of tents and other encampments. Contrasting the warmth of the city of Dis, Rubigo is cold and hostile to outsiders. The Devils from the city Dis regularly torment those consigned to Rubigo, chucking refuse, rubbish, and rocks over the walls of the city.

The city is run by a Devil known as "The Outcast" always seen covered in a ragged robe, their face obscured, with only two red eyes peering out. In reality, the outcast is Dispater's own archfiend daughter, Malachlabra. Disgraced after being nearly slain by the Simbul. As her eternal soul returned to the Iron City, she was turned away, banished by her own father for her failure. Now she plots her revenge from the great slum that is Rubigo.