You wake up with a start to the siren’s blares. Grabbing your weapon and armor, you head to the Battle Door, where your fellow adventurers are wearily mustering. You grab the handles bolted into the floor and brace for collision, which comes hard.
The magic mouth stops blaring, and then announces in that dreaded voice, “Prepare for Battle: The Rusted Blade versus Maglubiyet’s Children.” The doors open, revealing an arena of aerial ropes linking turret towers above a floor covered in metal spikes. Across the arena, you see the soldiers of Maglubiyet’s Children race towards the pivotal central platforms.
You sigh as your commander begins barking out orders. Just another day in Acheron.
Acheron is a plane of law, where the orders of one’s superior supersedes all personal desire, where battle rages across cubes, both on their outer faces and on the tunnels and battlescapes within. But what are the laws of conflict that govern the collisions of these cubes? In this article, we will re-imagine Acheron as a plane of hierarchical combat perfectly suited for combat-heavy adventures.
What’s missing from the official materials?
The official Planescape and DND 5e materials describe Acheron as a plane where iron cubes constantly collide with each other. Armies unceasingly muster and wage war on the outer faces of the cubes and on the tunnels that worm their way within.
On a philosophical level, Acheron seems to embody mindless obedience and conformity, as victory and ceasefire are impossible. The cubes collide with each other randomly, or at least the pattern of their collision is not provided by the official materials. Nor is it clear how one could purposefully move from cube to cube, or what ‘progress’ would look like in Acheron.
On the gameplay level, it supports scavenging through battlefields or being thrust into pointless struggles, perhaps as slaves, mercenaries, or unwilling participants.
But is this realizing Acheron’s potential as a plane embodying law and conflict? The battlefields of the Blood War on Avernus already provide the same gameplay options, while being set in a more interesting philosophical backdrop. Maybe Acheron is designed to be more accessible to lower level PCs than the fiend-ridden lower planes, but the plane still feels a bit lackluster.
Let’s see how we can spice it up.
Acheron: The Endless Tournament
Re-imagined, Acheron is an enormous, unending tournament where teams of combatants strive only to advance in rank through victory. At all times there can be only one champion, and that champion, like a professional boxer, must be ready to take all challengers, so few teams hold the belt for long.
Thus imagined, instead of Acheron’s inhabitants fighting for no clear objective, the objective now is to win. Unlike the Blood War raging in Avernus, where Demons and Devils hope to spread their ideologies of chaos and law, victory in Acheron’s tournament is not a means to an end, but an end in itself. Thus Acheron carves out a unique and interesting philosophical space within the outer planes, and allows GMs to explore the human drive to compete and game, and what winning means when determined within a system of arbitrarily defined rules.
How it works
Battle teams enter the tournament in one of two ways: by fighting a “collision” in Acheron’s gate-town, Rigus, or by winning sufficiently impressive victories in the name of one of Acheron’s gods. The latter is the chief method of entry for the Goblinoids and Orcs who make up many of Acheron’s combatants, while planars and primes typically enter through collisions. (Goblins and Orcs who die in combat in the name of Acheron’s gods also emerge in Acheron as petitioners.)
To enter a collision, one’s battle team must meet the legal requirements to lease a cube in Rigus. Cubes are physical headquarters for battle teams, equipped with beds, basic supplies, etc. The city is made up of thousands of cubes of various sizes which replenish themselves as the blocks of vanquished teams magically reappear in Rigus.
Once a team has acquired a cube, it must prove itself in lesser battles in Rigus until it is invited to participate in a collision, a formal match between two teams, officially fought until surrender, but in practice fought to the death, as most combatants value their pride over their lives.
The winner’s cube then launches into the plane of Acheron, where it collides with other cubes of similar rank. Victors move on and acquire spoils from the losers, including part of the loser’s cube, which merges with and enlarges the victor’s cube. After a certain number of victories, a combat team completes a level and arrives at a supply cube. There it docks for a designated period of time, giving the team the chance to purchase supplies, hire mercenaries, and buy slaves. Supply cubes also have portals back to Sigil or other locations in the planes to facilitate trade and adventures...or escape!
No holds barred arena combat
When two cubes collide in Acheron, combat does not take place on the cubes themselves, but rather on a third arena cube, into which both other cubes crash. Shortly before impact, a magic mouth enchanted on a huge, magically sealed doorway of the cube loudly blares a siren. Upon impact, the magic mouth announces both combatants (or up to 6 combatants, as some collisions involve combat teams colliding onto each face of the arena cube). This can be done in the boxing announcer Let’s get ready to ruuuuummble style, or in one that suits your fancy.
All sealed doors then magically open simultaneously, revealing the battle arena. Battle arenas may have tactically important high ground in the middle, secret caches of weapons or healing potions, devious traps, countdown effects like the release of poisonous gas that discourage trench warfare, or hostile constructs or monsters--basically, anything to increase the challenge and fun of combat.
They can be one large room or many rooms; an outer cube with tunnels winding within or an urban cityscape. Each arena cube need bear no resemblance to those before and after it; each is a discrete battle environment designed to test its combatants. This gives the GM leeway to create diverse environments without causing one’s story to feel disjointed or nonsensical.
The DM may organize collisions around the adventuring day. If parties only fight one battle on each cube, the party may collide with three cubes in one day; if each arena contains multiple discrete encounters, collisions may be less frequent. Battle is fought until death or surrender. After one side is defeated, the magic mouth loudly announces that the victor has a specified period of time to return to its cube, after which the cube detaches and again begins colliding up Acheron’s tournament.
Don’t forget the roleplay
Although re-imagined Acheron supports combat-heavy encounters, players should have opportunities for role-playing as well. Given Acheron’s philosophical underpinnings, I suggest exploring questions such as the morality of following orders, victory as an end in itself and not merely a means to an end, and the ethics of sacrifice.
Will the PCs kill enemy slaves who are forced to fight against their will, knowing that to spare them may mean putting themselves at risk? If a scenario gives the players an option to sacrifice one of their own, kamikaze-style, in exchange for a strong mechanical benefit in a battle, will they do it? What if their goblin opponents make a sacrifice and immediately gain the upper hand? Can the players convince NPCs of the pointlessness of the entire endeavor?
Acheron arena combats, like all Planescape encounters, should never be far removed from these philosophical and moral dilemmas.
So how do you throw the PC’s into Acheron?
Perhaps they are on a diplomatic mission or secretly investigating one of Rigus’s battle teams when the cube they are in suddenly launches into Acheron. They become reluctant conscripts, at least until they reach the first re-supply cube.
Or maybe they are slaves stolen from a Blood War battlefield or from the battlegrounds of Ysgard and made to fight against their will, allowing the GM to contrast different ideological conceptions of why we fight.
Or perhaps the players are just mercenaries who need the coin. PCs can enter Acheron at any of the supply cubes, so higher level PCs may enter at later stages of the tournament and receive commensurately larger compensation.
However the PCs enter, GMs should make sure that Acheron’s battle arenas are filled with challenging tactical combat and philosophical questions about the nature of obedience and sport.