Infinite Layers of the Abyss

Description
It is an infinity of clutching horror. It is the home of the tanar'ri. It is where morality crumbles and ethics perish. The Abyss is all that is ugly, evil and chaotic reflected in its infinite varieties through layers beyond count. Its virtually endless layers spiral downward into ever more atrocious forms. Conventional wisdom places the number of layers in the Abyss at six hundred and sixty-six, though no one has ever explored all of them. The Abyss is far more terrible than conventional wisdopm can encompass.

Each layer has its own unique and horrible environment. No theme unites the multifarious layers other than their harsh and inhospitable natures. Lakes of caustic acid, clouds of noxious fumes, caverns of razor-sharp spikes and landscapes of magma all exist. So are parched deserts that suck the moisture fron your body, subtly poisonous winds and plains of biting insects.

The Abyss is home to tanar'ri, creatures devoted to death and destruction. A tanar'ri in the Abyss sees visitors as food or amusement. Others see especially powerful visitors as potential recruits (willing or not) in their never-ending war against the baatezu known as the Blood War. Tanar'ri lords and deities inhabit the Abyss, including Demogorgon, Graz'zt, Pazuzu, Blibdoolpoolp, Diirinka, the Great Mother, Gruumsh, Hruggek, Lolth and many, many more. While the Abyss has layers beyond count, the top layer is well-known: the Plain of Infinite Portals.

Abyssal Traits

 * Normal Gravity
 * Normal Time
 * Infinite Size
 * Divinely Morphic
 * No Elemental or Energy Traits
 * Mildly Chaos-Aligned and Mildly Evil-Aligned
 * Normal Magic
 * No Special Traits

Abyssal Links
The two most well-known access points to the Abyss are a gate in the Concordant Domain of the Outlands from the town of Plague-Mort, and the River Styx. Both points provide access to the plane's topmost layer, the Plain of Infinite Portals.

Planars
Tanar'ri are the unquestioned rulers of most of the Abyss, though deities have carved realms for themselves and other evil creatures live here as well. Bebiliths, bodaks, retrievers, undead of every sort, renegade baatezu, twisted mortals and much worse inhabit this plane's infinite layers.

Petitioners
Those souls from the Material Planes that are not simply absorbed into the structure of the Abyss become petitioners called manes. Manes have pale white skin, cruel claws, sharp teeth, sparse hair, and white eyes. Often, maggots visibly squirm through a mane's bloated flesh. Manes that survive many years are sometimes "promoted" to lesser tanar'ri types, though they retain no memories of their former lives. They have the following qualities.
 * Additional Immunities: Lightning, Poison
 * Resistances: Fire 20, Acid 20
 * Other Special Qualities: Acidic Vapor, No Planar Commitment
 * Acidic Vapor: When a mane is slain, it discorporates into a cloud of noxious vapor. Anyone within 2 squares of a slain mane takes an attack (Level + 5 versus Reflex). Those who fail take 1d6/2d6/4d6 Acid damage.
 * No Planar Commitment: Unlike most other petitioners, manes can leave the plane they call home.

Proxies
No proxies significant enough to list reside here, though proxies almost certainly exist inside each realm.

Movement and Combat
In general, the Abyss functions like the Material Planes with regard to movement and combat. On layers where the environment is radically strange, different rules apply. Individual layers could have the fire-dominant trait, or have subjective directional gravity. Unless states otherwise, those traits function the same in the Abyss as they do everywhere else.

Plain of Infinite Portals
This is the topmost layer of the uncountable Abyssal layers. It is a barren, dusty place without life or greenery, baking beneath a hell-red sun. The dusty plains are broken by three features: huge pits in the earth, great iron strongholds and the River Styx.

The pits of this first layer are portals to deeper layers. Dropping down a given pit soon deposits the traveler into the associated layer, though jumping into random pits is insanely dangerous. It is 50% any pit is a two-way portal.

Iron strongholds here most often house powerful tanar'ri and their courts. Such fortresses either serve as rallying points for the demonic hordes on their way to join the Blood War, or protecting especially valuable pits or portals. Some of that war's greatest battles take place in this layer, deeper layers and nearby Outer Planes.

The River Styx flows a winding course on this layer. Some channels pour into pits, while other pits well up with the foul water, serving as tributaries of the mighty river.

Broken Reach
Red Shroud, a succubus sorcerer, rules the town of Broken Reach, which serves as a gathering point for Blood War mercenaries, a way spot for travelers insane enough to explore the Abyss, and a place for trade. The town is a set of crumbling towers surrounded by outworks of trenches, walls and spiky barricades.

Several important precincts are underground. The portal to Plague-Mort, a town in the Outlands, is beneath the main hall, for example. The food stores, the arsenal, the interrogation halls, and the crypts are likewise underground, connected by narrow tunnels. Rooms for visiting mercenaries and merchants are above ground, off the main towered hall. The inhabitants are a mix of petitioner slaves, tanar'ri of all types and mercenaries from the Material Planes and beyond.

Ferrug
An abandoned iron stronghold is situated near the Lakes of Molten Iron, a series of natural white-hot crucibles filled with molten iron. Ferrug's former tanar'ri lord was slain as she lay senseless while astrally traveling the Material Planes to corrupt mortal hearts. Since then, Ferrug has hosted countless armies of tanar'ri interested in gathering workable iron to build other iron strongholds. Because the tanar'ri highly value iron, baatezu strike forces often attack the Lakes of Molten Iron, so Ferrug currently serves as a command center for a force of tanar'ri charged by Demogorgon to protect the lakes.

Realm of a Million Eyes
The 6th layer of the Abyss is home to the Great Mother, whom beholders revere. The realm is a network of countless twisting tunnels, and living eyes stud the tunnel walls like encrusted gems. In fact, each eye on the wall is an eye of the Great Mother. Beholders and beholderkin of particular piety roam the eye-studded tunnels, preying on one another as well as any tanar'ri or other visitors who might accidentally come here.

Ice Wastes
The twenty-third layer of the Abyss is a bitterly cold plane of miles-deep ice, devoid of most life. A distant sun no brighter than moons on the Material Planes, lights this plane. The Ice Wastes are the province of the frost giants who serve Kostchtchie, their tanar'ri prince. Frost giant mages dwell with their prince in the Glacier Citadel, a fortress carved into the creaking ice between two towering peaks. Spring never comes to the Ice Wastes, and most of its inhabitants live in underground strongholds and caverns.

Azzagrat
Azzagrat is the realm of Graz'zt, an Abyssal lord. Azzagrat stretches over three layers, the forty-fifth, forty-sixth and forty-seventh. Because all three layers are ruled by the same Abyssal lord, they share many traits and have many portals connecting them.

One of the common threads among the three layers is the River of Salt, a sparkling crystalline mass of liquid salt crystal. Submersion in this river is lethal. Portals often appear as groves of viper trees and ovens of green fire; however, some of the ovens are full of fire, and will likely kill the uninitiated.

The environment of the three realms is not particularly dangerous; each resembles a twisted version of the Material Planes. For instance, the forty-fifth layer is like a constantly gray, rain swept steppe. The forty-sixth layer is illuminated from the ground, so that shadows are strange and rise like columns of darkness into the sky. The forty-seventh layer can only be reached from the previous two layers, never the Plain of Infinite Portals, is lighted by a blue sun. Here, flames are purple instead of red and they deal Cold damage. Thus, creatures normally immune to fire may be in for a surprise.

Zelatar
The largest city in Graz'zt's realm, it exists on all three layers. Doorways may allow entrance into a building or an exit to the street, but that building or street may be on a different layer. The inhabitants here quickly learn the ways of these shifting portals, but visitors will need a guide in order to navigate the city.

The Argent Palace is visible from anywhere within the city, regardless of which layer the observer is actually on. The Argent Palace is Graz'zt's abode of sixty-six ivory towers and one hundred cold, mirrored halls. The palace is a sterile, echoing place where those seeking an audience with Graz'zt must wend their way through the mirror and portal maze in which ravenous bodaks roam.

Demonweb Pits
The sixty-sixth layer of the Abyss is home to Lolth, the Spider Queen. The plane folds in upon itself so that it resembles a great web. A dizzying array of web tunnels interconnect with fractal complexity. Each strand is strung with portals onto the planes where Lolth is worshiped. Lolth's palace is said to be a mobile iron stronghold shaped like a spider, perpetually crawling across her planar web.

Smargard
The seventy-fourth layer is home to Merrshaulk, the yuan-ti deity. It is a realm of ever-shifting colors, moist jungles, acid rain and fermenting poisons. There may be no jungle floor at all, just layer after layer of darker and dimmer forest canopies.

Abysm
The eighty-eighth layer of the Abyss, called the Brine Flats, is home to Demogorgon, one of the most powerful tanar'ri princes. It is a realm of briny water and rocky prominences used as rookeries by flying tanar'ri. Aboleths, kraken and demonic manta rays war in the depths, but all bow before Demogorgon's might. Here, Demogorgon has his terrible palace, Abysm.

The portion of his palace above water takes the form of two serpentine towers, each crowned by skull-like minarets. Here, Demogorgon wields his arcane might, attempting to induce the very Abyss to vomit forth its secrets. The bulk of his palace extends deep underwater in chill and darkened caverns that have never seen light. The tanar'ri prince hoards his strength, only rarely involving himself directly in the Blood War. His designs go far deeper.

Thanatos
This is the 113th layer of the Abyss. It is a cold layer of ice, thin air and dreary moonlit sky. The layer belongs as much to the undead as the tanar'ri - in fact, the layer has the minor negative dominant trait. Still, fiendish mosses and fungi grow on the edges of crusty tundra. Tombstones of every imaginable and unimaginable type dot the frozen landscape, sometimes standing alone and sometimes grouped haphazardly as if in a small cemetary. Undead range everywhere.

Naratyr
Naratyr, called the City of the Dead, is a cold realm carved into the surface of a frozen ocean. Naratyr's icy architecture is a frigid necropolis of tall mausoleums, towering funeral obelisks, crypt parapets, and carpets woven of hair removed from the thousands of unquiet dead that reside in Naratyr. The city's warlike legions include retrievers, vampiric giants, and liches of all varieties. The rank and file of the population is mostly zombies, ghouls, wights, and other decaying corpses that move with a dark purpose.

Who rules this city? A good question. For time out of mind, a powerful tanar'ri named Orcus ruled this layer. However, Orcus was recently declared slain. A drow deity of vengeance and undeath claimed the layer in his absence, but now there are strong hints that rumors of Orcus's death were greatly exaggerated. The drow deity is gone, and no one knows if she fled or was slain. Could it be Orcus has returned to regain his throne, one bony hand clutching his terrible rod?

Slime Pits
The two hundred and twenty-second layer is home to both Jubilex, the Slime Lord, and Zuggtmoy, the Lady of Fungi. The layer is a bubbling morass of oozing, fetid sludge called the Amoebic Sea. Vast expanses of caustic slime engender strange life forms, sometimes by the will of the tanar'ri who reside here, but sometimes spontaneously.

Fortress of Indifference
The three hundred and forty-eighth layer is a lonely, blasted plain of tumbled rocks jagged pinnacles, and sinister gorges devoid of natural life. Crimson clouds scrub the sky, and freezing winds lash a traveler's eyes and skins. Here stands the Fortress of Indifference, a single two hundred-foot-tall tower of black iron gridwork. Humanoids of every variety are woven into the metal itself, used as a ghastly mortar. Most of the forms are dead, but many are undead and constantly wail and claw at the air.

The Fortress houses outcast tanar'ri, half-fiends and tieflings. Though these creatures are evil through and through, they have turned their backs on the Blood War. A nalfeshnee tanar'ri named Tapheon rules the Fortress. Tapheon's form is horribly scarred, and he constantly wears a body brace of rusty iron that keeps his bloated form upright with long hooks.

Tapheon's favorite toy is a magic rod called the Despoiler of Flesh, fashioned from sewn-together tongues. With it, Tapheon can alter any creature's shape to any other he can imagine. Of course, the imagination of a tanar'ri is a foul thing, and he has used it to bring ghastly creations to life.

Noisome Vale
The four hundred and eighty-ninth layer was once ruled by a powerful balor named Tarnhem, though he has gone missing. The layer's atmosphere is a haze of acidic gas constantly regenerated by volcanic vents that scar an utterly blasted landscape. A ravine cuts through the landscape of the layer, but it is not filled with water or condensed acid. Instead, it channels a flood of slick, writhing worms that vary in length between one inch and ten feet. These worms inhale the sulfur fumes endemic to the layer and exhale breathable air. This air essentially makes the area within fifty feet of the ravine breathable.

Tarnhem's manor is built along the ravine. Thanks to the worms, it possesses a breathable atmosphere, though the constant squirming of the worms below can be maddening. Tarnhem's tanar'ri staff still maintains the manor despite his long absence, as they believe he is imprisoned off the plane somewhere. Despite all of this, the tanar'ri that guard the manor take a dim view of unannounced visitors.

Abyssal Encounters
Roll once per hour on this table for encounters.