The Planes: Acheron
Our next stop in The Planes series is Acheron- a plane of order, law, and eternal battles.
Introduction to the Planes
Reflections: Feywild, Shadowfell
Inner Planes: Elemental Chaos, Plane of Earth, Plane of Water
Outer Planes: Astral Plane, Beastlands, Gehenna, Mechanus, Mount Celestia, Pandemonium, Sigil
What is Acheron
Manual of the Planes, 2001 WotC
Acheron is an iron-shod plane that is known as the Infernal Battlefield or the Infinite Battlefield. The plane is home to the constant battles and wars without meaning, rebels without causes, soldiers who love to fight whether they have reason to, and the hordes of goblins, hobgoblins and orcs warring between themselves. Archeron is located between Mechanus and the Nine Hells, making it the most lawful of the evil planes. While most might point towards the devils and the Nine Hells as being the ultimate idea of what law and evilness should look like, Acheron is more lawful and not quite as evil. Acheron is the home of those who commit evil but only secondarily, their main aim being order and law enforced on those who don’t follow their set laws.
There are four layers in descending order Avalas, Thuldanin, Tintibulus, and Ocanthus; with the topmost layer being the most habitable and the bottom layer being the least habitable, which is a common trend among all Outer Planes as even Mount Celestia’s highest slopes aren’t fit for the normal adventurer. Each layer is composed of massive shapes floating around in the atmosphere, they crash into one another destroying anything on their surfaces and continue their endless drifting. Across every block are the massive armies waiting for their block to come in contact with another and they can continue their endless wars.
History
Planes of Law, 1996 TSR Inc.
Acheron is introduced in 1st edition, and it stays the same throughout every edition thereafter except for 4th edition where it no longer exists, though 5th edition provides almost nothing beyond it is made up of four layers with floating iron cubes. The plane is depicted as a plane of pointless battles and wars, that those who become petitioners of this plane, the souls who are in their eternal plane of rest, are the ones who reveled in battle regardless of ideals, who rebelled for no reason, and who brought order and law through violence.
The plane is focused on the group, rather than the individual, and only a handful of gods make their home on these iron cubes. The gods who do claim dominion over areas of this plane are the gods of goblins, hobgoblins, and orcs, though the goblinoid races are in constant war with the orcs for control of the cubes.
An Outsider’s Perspective
Compared to most other planes, Acheron is a wasteland though it holds that position along with several other evil planes. Visiting this plane is not for the faint-hearted as most portals are not actually on land, but rather leaves you floating in space and ‘falling’ towards the closest cube. Of course, if you have no way to halt your fall your first ‘step’ will be more a splat as you slam into a cube. If you can survive the fall down, all you have to worry about next are the ferocious battles that are constantly taking place across the first layer, Avalas.
The sounds of battle, and the slamming of cubes, is constant in this plane as the noise echoes from cube to cube. Those who visit this plane have a very specific reason for being here, and quickly deal with their business and promptly leave before they are ‘hired’ as a mercenary, impaled on spikes because the Mercykillers think you broke a vague law or enslaved by a moving city and forced to become part of the living walls. Creatures of good or chaotic alignment would find this plane to be appalling, but for those who crave war for the sake of fighting, for carrying out orders without regard to its purpose, and for imposing your power over others, this is a violent heaven.
A Native’s Perspective
Planes of Law, 1995 TSR Inc.
This plane is considered a safe place for many to visit with the devils of the Nine Hells and is untouched by the Blood War. There is an enforced order through conformity, with little thought if that conformity is good. Armies wage war against each other, their only objective is the destruction of each other and the imposing of law and order on the other. There is little thought of accepting others for their differences, and in fact, that type of thinking is tortured out of creatures who try to express it.
The creatures who live here are those who loved to battle, regardless of why they warred. They roam these massive geometric shapes, waiting for when they may crash into another cube drifting through this plane and lead a charge against its inhabitants. The strongest armies on this plane are the armies of goblinoids and the armies of the orcs and its not surprising that they are constantly waging wars and striking at each other. The goblins despise the orcs and their lack of law, while the orcs are led by their god trying to find a home somewhere in the planes after fleeing from Gehenna and the Nine Hells after trying to take on more than they could.
Apart from the goblinoid and orc petitioners are the petitioners of duergar whose original deity who was exiled from the other dwarven deities in Mount Celestia, and they are a grave and somber lot who live on the second layer, Thuldanin. In their duergar city, they are constantly producing weapons to help protect themselves from the monsters who roam Acheron. The other major faction on this plane is the Mercykillers who see mercy as weakness and weakness as death. They are after order and punishment, for only punishment breaks the souls of those who would go against the group and against the order.
Absolute Souls
Many claim that every effect on Acheron has an opposite and equal effect. If you cast a fire spell, a cold spell somewhere else in the plane goes off as well. If a creature dies on the plane, another creature is born to this plane. Many go on to assume that the number of creatures on this plane is therefore finite and that you can never have more creatures on this plane than the set number, though no one knows what the number is. Many armies take this to heart and have decided that the only way to grow their numbers is to cause war and kill everyone that is not them, thus allowing more of their own petitioners to join their ranks.
Other creatures think this as well, except that they think this only applies to the petitioners, those who are already dead and it is their soul that has come here for their eternal resting place. Mortal creatures, like humans from the Material Plane or elves from the Feywild, do not count against the number of absolute souls allowed on the plane at one time, and thus many armies will hire mortals to be mercenaries… or if they mortals don’t wish to be mercenaries, they will simply press them into slavery and force them to fight for the army instead. Many see this as a loophole so that they may grow their army without having to lose any of their petitioners, only mortals who are only useful as being expendable.
Atmosphere
The atmosphere of this plane is much like the Material Plane, though the light is never brighter than a dull, overcast day and gets as dim as a full moon. No one is sure where this light comes from, but its dim shining can be seen everywhere. When cubes pass in front of the light, it causes beams of light and shadow, making many think there is a cube out there who glows with intense light, but its an infinite distance away as no one has ever seen it.
The natural hazards of this plane come mostly from the floating geometric shapes that will routinely crash into one another, destroying anything that is unlucky enough to exist on the surface of the blocks. Most creatures and armies have made their homes inside of the iron blocks where they are protected from being smashed into oblivion, though cave-ins still pose a threat. The most dangerous layer due to its atmosphere is the last layer, Ocanthus, as it is filled with flat shards of black ice that are a few inches to a few miles across. They shoot forward with great speed at all sorts of angles, causing any creature who arrives on the bottom layer to become punctured with hundreds of wounds in a matter of minutes or have their head sliced off if they are truly unfortunate.
The weather on this plane is aptly known as brooding, with its gray light and cold winds that howl through the plane. Blizzards and ice storms fed by the River Styx on the first layer can cause horrible problems for the armies during their battles, and the iron cubes that make up every layer suck all the warmth out of those who live here.
Planes of Law, 1995 TSR Inc.
Traits
Travel to the Plane
Arriving on this plane is can be done through portals from the Nine Hells or Mecanus, though many of these portals are free-floating and thus when a creature appears, they appear in the middle of nothing and begin falling to whatever surface is closest to them. There are a handful of portals that are locked to specific cubes, though they are heavily guarded by armies and any trespassers, which is everyone not part of that group, is either enslaved or killed if they dare resist. Of course, you could also journey to this plane by paying the ferrymen to take you along the River Styx as it moves across the top layer of the plane and is even said that it ends at the bottom of this plane, though no one has been able to prove it.
If you are able to locate a portal on this plane, they appear to be spherical and when you touch them they emit a chord of music. A harmonious sound means the portal will take you to Mechanus, while a discordant sound means the portal leads to Baator, the Nine Hells. If the sphere makes no noise when you touch it, it will take you to the Astral Plane. These portals exist free of any cube, though they are locked into a specific space in the plane and must typically be reached by a creature who has the ability to fly. Of course, sometimes these cubes will pass through the space of the portal, in which case you can access the portals quickly, though they do not work as they are passing through a cube.
Traversing the Plane
Planes of Law, 1995 TSR Inc.
Traveling through this plane is simple, so long as you pay attention to where the other geometric shapes are located across the plane. Many armies, so focused on battle, will find themselves smashed to oblivion as another cube slams into the one they are fighting over. While these two cubes are knocked into each other, a quick traveler can cross on to the next cube by simply stepping over to the other cube, gravity always pulls a creature to the center of the cube, making it easy to walk along the sides of the cubes.
Each cube is large enough to hold a city or large enough to hold kingdoms, many say that the smaller the cube, the older it is as it slams into the others, slowly breaking itself up into smaller geometric shapes. There are several massive cubes that show little damage or cracks, and many assume those cubes are new and to be avoided as no one has mined through the iron cube and made tunnels to protect yourself from collisions. Most cities exist on the inside of cubes, though gods have the power of pushing other cubes away from theirs.
The top layer cubes are made of solid iron and you must mine your way into the cube in order to start up a settlement. The second layer, Thuldanin, is made up of hollow cubes and following pits into the cube you can find mountains of old machinery that have been turned into stone. The third layer, Tintibulus, is made up of hundreds of different geometric shapes all floating through the void, the more they crash into each other, the more they form smaller, more complex geometric shapes. Finally, the fourth layer is made up of flat shards of black ice that range in size from a few inches to a few miles wide and long. Due to their impossible thin thickness, they are dangerous and capable of slicing through metal as if it weren’t even there.
The Birds
On the top layer, Avalas, are massive flocks of birds who fly from cube to cube. These flocks watch for battles and feast on the dead bodies leftover and many see these flocks of sparrows, hawks, buzzards, ravens, pigeons, and more as signs of good luck… though if birds are ever encountered as solitary, that is a sign of horrible and bad luck and there are complicated rituals used to be rid of bad luck.
Locations
Avalas, the Battleplains
No matter where you travel on this layer, the sound of close battle and distant colliding iron cubes is indistinguishable. This layer is the most populated, due to having the most iron cubes, and fortresses and cities have been built inside of almost all of the cubes. The wreckage of war litters the ground of most of these cubes, only cleared away when two cubes collide into one another and destroy anything on the surface.
The River Styx travels haphazardly across this top layer, erupting out of one pit, traveling across multiple sides of the cube before disappearing back into another pit, only to reappear on a distant cube. Occasionally, the River Styx will shift its direction, and a fortress set up near the river will be flooded and destroyed by its waters, anyone caught in the grimy waters losing their memories and personality in its floods.
Devils from Baator, Yugoloths from Gehenna and Hades, and the occasional demon from the Abyss can be found on this plane, searching for battalions to fight in the Blood War. The gods who live on this plane are focused on growing their armies, sending goblinoid armies marching against the orc armies, all the while hundreds of smaller armies march against each other on the distant cubes floating through this world. All problems that any army faces on this plane is that there are few leaders, as they are called to other planes due to most leaders not having the suitable inclination of bloodlust.
Clangor
Planes of Law, 1995 TSR Inc.
The home cube of the goblins, this cube is riddled with uniform tunnels and caverns created by the goblinoid deities. This cube is one of the few with towers sticking out of it as the deity in charge can easily push other cubes away from colliding with the battlements. The towers, along with the trenches and other fortifications, make this cube a highly dangerous target for anyone to lay siege too.
The tunnels are dug to exact measurements with two types of tunnels, the normal tunnels that are perfectly round and large enough for most humanoids to easily walk through and the tiny tunnels that only goblins can squeeze through one at a time. These round tunnels all end up in square caverns filled with bunks, armories, supplies, and even more. On many sides of the goblinoid cube are the goblin and hobgoblin towns and cities, the largest being Shetring where their deity resides. In every city and town, strict hierarchies are observed and all goods are made to exact measurements, from the thickness of a wool cloak to the quality of a sword, all are made to exact measurements. Anywho try to sell off lower quality goods, and sometimes even higher quality goods is up for abuse by the officers of the goblin army.
Nishrek
The strong rule while the weak die is a motto of the orcs and their cube echoes that sentiment. Ruled over by their deity, who some call Gruumsh, these orcs have been searching for a home out in the planes and have recently settled on Acheron after being driven from Gehenna and the Nine Hells. The orc deity is known for taking on fights that they can’t win, and many assume that the orcs will be driven out of Acheron as the orcs just aren’t lawful or orderly enough to survive here.
Inside the cube are the battlements of orcs and their war chiefs, everyone here is constantly fighting not only with the armies on this plane but with each other in order to gain higher roles in the military. Most orcs live in trench towns, these trench towns are carved into the cube in specific lines and dug down to have small buildings and barracks existing a few feet from the surface. The stronger orcs live in cities across the cube, in specific locations. The strongest of the archers, the shamans, the spearmen, and the siege engineers all have their own blocks so that they are separated from each other and live apart from one another. Only orcs, ogres, orogs, and certain yugoloths are tolerated here, while all others are ripped apart by the orc hordes.
Istvarhan
This mobile city is partly alive and partly iron, it moves about on massive skids that are pulled forward by the slaves who live inside of its iron walls. These slaves are captured from all over the layer and forced into service by the city, most of these people were criminals wanted for breaking one law or another, though that isn’t always true. The strongest among the slaves can last for years before they eventually become too weak to push the city forward and stumble down, collapsing to the ground and becoming the grease that helps the city skids slide over the cube’s face.
This city is ruled by a half-orc and his orc and orog commanders, and the city is one of the last of its kinds, known as a hassitorium. These hassitoriums were created by an ancient and, probably, long-dead race and no one knows more than that. There have been previous hassitoriums, as evidenced on the second layer of the plane, but no one is sure when they were created or how this long-dead race created them.
Vorkehan, the City of Fumes
Planescape Campaign Setting Box, 1994 TSR Inc.
The home of the Mercykillers and their creed that mercy is weakness, and weakness death. They seek to punish those who break the laws, no matter how unjust the laws might be, and provide the harshest sentences when possible. Their theory is that if you punish someone so severely for any slight crime, they are less likely to repeat their mistakes for future crimes. The Mercykillers believe that any who breaks the law is misguided and if you kill enough martyrs, those misguided rebellions will collapse.
The city is a fortress built on the corner of a cube, with large iron walls bolted and fused together. The streets are laid out in perfect uniformity, the streets made of titanium and the gutters of lead. The fountains set in perfect order throughout the city gurgle with bubbling acids, producing a horrible smoke that causes most creatures, except those who live here, to double over and wretch from its horrible smell. Because the city is built on a corner of the cube, when walking across the city you will have to walk 90 degrees from one side to the next, all the while the most powerful winds of the cube are trying to rip you out into the void. Many newcomers have simply fallen off of Vorkehan, the winds carrying them out into the nothingness of the plane.
Visitors to this city must always be on their best behavior and knowledgeable about every law. Those who break it are immediately captured by the guards and brought in for questioning. Because of who the Mercykillers are, they assume anyone captured by the guards is guilty and their questioning is more to determine how severe the punishment can be. Most crimes are punished by lashing, by hanging or by being forced into the army of the Mercykillers, though if you can beg and plead well enough, and bribe the judge, you can escape with a lighter sentence.
Thuldanin
Appearing to be much like the first layer, the second layer is far less populated and there are fewer cubes floating in its space. The iron cubes here are all hollowed out, their insides filled with the discarded machinery of war. You can find airships, spelljammers, catapults, massive castles, and technology that has yet to be invented, all lying broken and in tumbled heaps, slowly turning into an ironlike stone as they decay. Scavengers from Avalas hunt through these cubes, searching for something still useful and not petrified to stone by this layer.
Every object, and creature, that enters this plane is under a strict timeline. Anything that exists in this layer for more than a few weeks is turned to stone, with the hardiest creatures lasting just a bit longer than that. Scavengers quickly enter this layer and then leave as quickly as they entered, not sticking around for fear of their equipment turning to stone or them turning to stone. The only creatures who seem unaffected by it are the duergar who have made their home in one of the cubes, as well as the rust dragons and other horrifying creatures who call this layer home.
Manual of the Planes, 2001 WotC
Hammergrim
The home of the duergar, these dwarfs were exiled from Mount Celestia and only found a home on Acheron. Here they work within the gray light and somber atmosphere of this plane, crafting their weapons to be used in the protection of their city against the monsters that lurk throughout this plane. Hammergrim is built for defense, and their duergar are only interested in defending themselves and looking after their own kind. They are willing to trade, but those who visit them must bring a lot of gold to convince them that its worth dealing with.
Visitors to this city may complain about the hammering and clamor of this city, but when it comes to night time all noises stop. Many of the duergar are afraid of making noise at night for the evil rakshasas have been known to kidnap the duergar and force them into slavery for the rakshasa’s and their clans.
Tintibulus
The third layer of Acheron is filled with even, geometric shapes that are 8 sided, 10 sided, 12 sided, and more. These shapes crash into each other, breaking and shearing on fault lines and producing even more geometric shapes floating through the layer. These blocks are made of a solid, grey and stonelike material like the stone produced by a volcano. These shapes are constantly ringing against each other, causing any who visit this plane to be nearly deafened by it. There is no natural life on Tintibulus and any who live have made their home here has long gone insane. According to some, wizards who are in deep study can be found in this layer, though no one knows how true that is or what they could possibly be studying.
Ocanthus
The fourth, and final layer, of Acheron is the strangest of the layers as it is filled with incredibly thin sheets of some sort of black ice material that can be a few inches across to miles across. These thin sheets of ice shoot all over the plane, slamming and colliding with other shards and creating more and more shards that zip across the plane, slicing and tearing into anything that gets in their way. Many visitors who arrive here are instantly punctured by these shards, with the unluckiest being beheaded by an unseen shard. This plane is coated in darkness, keeping these already hard to find slivers of black ice impossible to find for most creatures.
The River Styx
It is said that at the bottom of this layer is the final destination of the River Styx, and it is here where all the memories that the river has stolen end up, sealed in the black ice. No one knows this for sure, but rather it is supposition as the River Styx ends on this plane. Some even claim that this is actually where the headwaters of the River Styx come from, and somehow makes its way over to Pandemonium where the river forms.
Factions & People
Bladelings
Manual of the Planes, 2008 WotC
Hidden in a secret city on the bottom layer are the bladelings, a strange race of creatures who appear to be living metal. These strange creatures had searched for a home across the planes and eventually found themselves on Ocanthus where many of them died in order to build a safe home here. It is reported that any strangers to the city are caught and then sacrificed to dark gods, though no one is sure if those reports are true or else how did those rumors start?
Goblinoids & Orcs
These races are at constant war with each other on Acheron, their philosophy on law, order, and power is all the difference these two races need to begin attacking and battling each other, their deities pushing them forward in an effort to destroy more of the other so that their armies can grow larger. The goblinoids are easy to visit and can make great trading partners while the orcs kill and brutalize any visitors to their cubes. These races are locked in an eternal war on this plane, and many assume that the orcs will lose this war as they have lost on the planes of Gehenna and Baator, the Nine Hells.
Modrons
Found on the lower layers, these curious creatures hail originally from Mechanus but can be found mining out the great iron cubes that float through the layer. They are harassed non-stop by the other armies, though the modrons rarely take part in the wars here. Their numbers have been greatly hurt when their god, Primus, was killed by another and one of their own, a secundi, betrayed them and took over a million strong modrons to this plane. Some believe that the modrons can only create more of their own and more of the cogs by gathering the raw materials from this plane.
Rakshasa
Clans of Rakshasa have made their home among the multitude of cubes, hiding their palaces and homes behind powerful illusion magic. Here, they are ruled over by the maharajah, and many of the rakshasas seek to gain his approval by kidnapping strange and wonderous creatures from across the planes and force them to be slaves in their palaces. They take no part in the wars that echo throughout all of Avalas, but rather watch from a distance, enjoying the view.
Rust Dragons
These massive rust monsters have evolved slightly to be massive in size, and they search across Acheron for more food to feed off of. They are attracted to the battles and war, as many of the equipment used is made of metal and oftentimes is magical in nature. Many armies are forced to also have wooden and stone weapons and equipment, while less effective against other armies, are very useful in beating back Rust Dragons that get too close. Many armies will hire adventurers to deal with these troublesome creatures so that they can focus on their war.
Encounters
Rusting Weapons - A rust dragon has found its way to the first layer and destroying the armaments of the army. They are offering a large reward to any who can dispatch such a beast.
Grave Punishments - A companion of yours has been taken off the streets of Sigil and brought to the Mercykiller’s city on Acheron. Tougher punishments the Mercykillers claimed as they dragged them away, you must travel to Vorkehan and bribe the judge for a lighter sentence, failing that - breaking them out and escaping the clutches of the Mercykillers.
Lost Modron - A modron has stumbled out into the Material Plane, lost and unsure how it arrived on the plane. It must return to its companions on Acheron where it was mining a cube or face punishment by its superiors. It’s offering knowledge of a magic item it found on the cubes and had set aside for further tinkering.
Murder of Crows - Crows have been following you as you have walked across the side of a cube, forming a huge mass high in the sky above you and seem to be quite occupied with watching you. Its not until that the light gets darker that you realize the flock of birds were hiding a massive cube heading straight for you, and you only have a few minutes to get to safety before being crushed by a massive cube. Others might call you crazy, but you are confident that these birds purposefully hid this cube from your view.
Bladeling in Sigil - The strangest sight in Sigil has everyone gossiping. A bladeling appeared in a tavern one night, looking and searching for adventurers willing to travel to Ocanthus and help the bladeling city deal with a problem of dark gods. Most people have never even heard of a bladeling, nevermind that they have a secret city.
Resources & Further Reading
Manual of the Planes (1st edition)
For information on an earlier Acheron.
Planes of Law (2nd edition)
For more information on locations, the layers, and inhabitants of Acheron as well as potential adventures on Acheron.
Manual of the Planes (3rd edition)
For more information on the layers and locations of Acheron.
Deep Dive - The Rakshasa
For a consolidated look at the Rakshasa through the various editions.
Deep Dive - The Hobgoblin
For a consolidated look at the Hobgoblin through the various editions.
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