Oppressive darkness, howling winds, and the threat of madness lurk in the maze of tunnels that make up the Windswept Depths of Pandemonium. Pandemonium sits at the intersection of chaos and evil on the Great Wheel and is similar in many ways to the Plane of Earth in the Inner Planes. Both are comprised largely of solid stone, with cavernous pockets and twisting tunnels cutting through the rock.

However, while the Plane of Earth has little natural light and still air, Pandemonium is filled with cacophonous winds and pitch blackness. No natural light exists in the Windswept Depths, and the driving wind snuffs out torches with ease – even magical light is dimmed and unreliable as some latent property of the plane inhibits all illumination.

The winds of Pandemonium are more than gentle breezes. They howl like a living thing, careening down and around through tunnels made smooth by the constant windstorm-strength gales. Talking and hearing are difficult anywhere on the plane, and the oppressive darkness makes vision unreliable. Every natural element of Pandemonium is designed to isolate creatures and leave them feeling powerless and alone.

Madness is a constant threat on the plane, a madness driven by the constant howling of the wind, the chill air, and the sense of isolation brought on by the makeup of Pandemonium. Native creatures to the plane are usually deaf and blind, relying on supernatural or heightened senses to find prey, and demons are often found lurking in the darkness.

It is no wonder that Pandemonium is the least populated of all the Outer Planes. There are only a few scattered points of civilization, and most of these are filled with desperate, huddled beings gone mad from the nature of the plane. The largest population of people refer to themselves as the Banished, and they are the only native sentient beings. Humanoids of all types are found among their numbers, and they share a simple trait – they have embraced the madness of Pandemonium. They are dangerous, disorganized, and unhinged, but they know the tunnels better than anyone.

Monsters of all types prowl in the darkness. These include the gloomgaunt, loathsome bat creatures at one with the shadows, and the giant olms, toxic albino salamanders always looking for fresh meat. Cave goats, giant blind star slugs, and fearsome monstrous insects also crawl in the darkness. The River Styx winds through the upper layer of Pandemonium on its tour of the Lower Planes, and many monsters hide in the waters, knowing that the river provides regular traffic into the otherwise desolate tunnels.

Pandemonium also hides dark and terrible secrets in its depths. The planar walls between the Outer Planes and the dangerous Far Realm are thinnest here, and many planar scholars point to the Far Realm as the source of Pandemonium's wind and madness. Enormous creatures born of titanic nightmares ooze through the lower tunnels of Pandemonium’s depths, ancient entities from lost epochs beyond time and space. Some caves are filled with ruins of lost cities.

Safety and comfort are nowhere to be found in Pandemonium, and travelers who let down their guard in the Windswept Depths invite madness and death. Nonetheless, there are treasures and wonders to be found across the cavernous layers. Idols and obelisks dedicated to loathsome Far Realm entities can be found in far-removed places, offering hints to greater blasphemies just outside the planar borders. Cursed black diamonds, though rare and powerful, can be found under the right conditions in the darkest tunnels.

Getting There

The powerful winds that blow through Pandemonium have been known to gust strong enough to rip temporary gates through the planar barriers. Usually these lead to one of three places – the Plane of Air, the Plane of Earth, or the dangerously alien Far Realm. Thankfully, these gates are temporary and the breaches are often sealed before things crawl through, but not always.

Permanent portals to Pandemonium usually exist deep underground, and activating them often requires making some sort of loud noise. This can often draw unwanted attention so travelers looking to get to the Windswept Depths had better be prepared to face whatever wanders nearby when trying to find the right portal key.

The most reliable means of transportation into Pandemonium is via the River Styx. The blood-red waters wind through caverns, tunnels, and passages in a twisting, nonsensical pattern throughout Pandesmos, the top layer. Many of the monstrous predators lurking in Pandemonium’s perpetual darkness have learned to watch the River Styx and its various tributaries for fresh food, though many merrenoloths ply the river and know a trick or two to keep the hungry beasts at bay.

Traveling Around

A traveler must be able to navigate through the tunnels of Pandemonium in darkness. Carrying a light of any kind is ill-advised, especially in the meandering passages between the larger tunnels. The monsters lurking across the plane are drawn instinctively towards light, and the howling winds make anything but magical light impossible to keep lit.

Once the problem with sight is dealt with, a traveler must deal with the deafening noise of the wind. Shouting is the only way to be heard, though the driving wind means the native monsters have dulled senses of hearing, so the increased noise shouldn't attract unwanted attention.

Beyond the darkness and the shrieking wind, madness and isolation must also be dealt with. Sanity is fleeting in the Windswept Depths, and those who embrace madness often find themselves lost and utterly hopeless in the eternal tunnels.

Most of the tunnels and passages are free of impediments, making actual travel the least problematic part of the plane. The top layer of Pandesmos has very wide tunnels big enough for flying ships and great winged beasts, and the trend continues through much of Cocytus with its strangely worked stone chambers and tunnels. However, most of Phlegethon is not so wide, and many of its stone arteries are barely wide enough for humanoids to walk single file.

Lay of the Land

The entire plane of Pandemonium is contained within an infinite solid mass of stone. This physical nature leads many planar scholars to theorize a link between the Plane of Earth and the Windswept Depths, but the idea is based on little actual evidence, and it certainly doesn’t account for the constant, howling wind that blows through every single tunnel and cavern. No passage is devoid of the shrieking wind.

Pandemonium is divided into four layers, though the barriers between them are ill-defined at best. They are marked largely by the size and nature of the honeycombed tunnels, from the first layer Pandesmos (with many large tunnels) to the lowest layer Agathion (absolutely no tunnels).

Pandesmos

The top layer of Pandemonium contains the largest number of caves, some hundreds of miles wide, with the wind blowing constantly through it all. Some latent property in the stone on Pandesmos makes gravity behave strangely – creatures and travelers can move along the floors, walls, and ceilings with equal ease. The River Styx winds through portions of Pandesmos, creating an easy and navigable route into and out of the plane. However, it too obeys its own gravity laws, and in the same cavern can flow up the wall, over the ceiling, and down the other side without spilling a drop.

One of the few permanent settlements on Pandemonium, Madhouse, sits in an enormous cave on this layer. Flickers of magical light dance in the crowded streets, winking in and out of existence, adding to the city's mysterious allure.

Madhouse

Madhouse serves as one of the few points of civilization on Pandemonium, but it is by no means a safe place for travelers to visit. The cramped streets and buildings of Madhouse crowd over one another along the walls, floor, and ceiling of the cavern that holds it.

There is no singular organization to Madhouse, so each building exhibits unique architectural and design qualities designed only to satiate the builder's appetite for applying order to chaos. Leaning towers, crumbling citadels, abandoned warehouses, and more line the crooked, unpaved streets. Garbage and litter lay strewn about everywhere, constantly blowing about in the frigid winds, and everyone keeps a close eye on themselves, their neighbors, and especially any strangers who come to visit.

A few taverns and inns cater to outsiders, but many residents are deaf, insane, or both. Poison masters, trapsmiths, retired thieves, skilled assassins, burglars, and other larcenous types round out the population who otherwise mostly keep to themselves. No single authority rules Madhouse, though there have been attempts in the past to bring order to the town – these efforts seem doomed to fail at the outset, owing to the chaotic nature of Pandemonium and erratic behavior of the citizens.

Cocytus

The tunnels of Pandemonium narrow considerably in Cocytus, creating more dangerous windstorms that bring death and madness. Much of this layer has the appearance of ancient worked stone, and some planar scholars believe the barriers between the multiverse and the alien Far Realm are weakest on Cocytus. The worked stone of the tunnels and caves may be remnants of Far Realm cities, and the titanic ruins of Shothra, a city of elder things, are tucked away somewhere. Unfortunately, the tunnels also carry the greatest number of loathsome slimy monsters, such as shoggoths, oozes, and other foul monsters.

Phlegethon

The caves and tunnels of Phlegethon are just as dark as the rest of Pandemonium, but they are accompanied by a persistent slimy wetness over all surfaces. Many caverns on Phlegethon hold stalactites and stalagmites of monstrous proportions, though no rivers or obvious explanation for the condensation have been found. The only other community of note on Pandemonium, Windglum, is found on Phlegethon, built around an enormous stalagmite.

Windglum

Suspicion and greed mark the inhabitants of Windglum, a city of Banished in a great pillared cavern in Phlegethon’s depths. Squat buildings surround the stony columns that support the ceiling, and the people live in isolation and fear. From one another, from the monsters that lurk in the tunnels, from the threat of the Far Realm, from cultists, but mainly fear from an authoritarian power called the Order of Lords that rules over Windglum.

The Order of Lords is a mysterious, masked group that largely takes a hands-off approach to Windglum. They occasionally send their armored knights in black plate armor to patrol the city or crack down on a particularly loud rabble-rouser, but for the most part, these legions are devoted to protecting the interests of the Order of Lords. Their exact interests are vague, however, and few in the city have actually dealt directly with them. All manner of fiends and other creatures have been seen coming and going into and out of the Citadel of Lords, though.

Goods and services can be found in Windglum at about twice the going rate, or three times the going rate for outsiders. They manufacture little, and very few merchant companies make the journey through Pandemonium to reach the remote settlement. The ones that do deal directly with the Order of Lords who “confiscate” certain items before letting merchant caravans in to sell their stuff to the general stores and markets of Windglum.

Windglum does have one popular spot for planar travelers – the Scaly Dog Inn. It’s always been the spot the locals direct outsiders to, forcibly at times, and for a long time, the Scaly Dog had a deserved reputation as a haven for rogues, thieves, murderers, and cutthroats. It is currently owned and operated by an exiled githyanki warrior named Gimcrack, who has tried to turn the Scaly Dog’s reputation around and cater to the adventurers and travelers that come to Windglum ahead of expeditions deeper into Pandemonium. Gimcrack has worked to upgrade many of the inn’s amenities, and it’s staffed with transients since the local population won’t have anything to do with it. Rumors persist that there’s a connection to the famous World Serpent Inn somewhere in the Scaly Dog, and Gimcrack is determined to find it and exploit it. But it’s just a rumor so far.

Agathion

The lowest layer of Pandemonium is referred to as Agathion, and here, no tunnels are found. It is a locked layer of isolated cavernous pockets filled with stale air or dangerous void material and perhaps entities and powers exiled from the rest of the multiverse. These pocket realms are accessible only through portals or by tunneling through the endless stone, though attempts at blinding digging into Agathion have resulted in numerous cave-ins and sudden disappearances.