Out With the Old
The Howling Caverns
This plane is an endless underworld, a honeycomb of tunnels and caverns. Pandemonium is a strange realm where many outsiders, particularly those already afflicted by madness, appear instead of at the threshold of their god’s dominion. These poor souls are known as the banished, and kindly and valorous gods such as Pelor and Bahamut often stage rescue missions to retrieve the banished and care for them. Gravity orients to any wall of the tunnel, so a wall for one visitor is a floor for another. One can even “thread the needle” and float down the dead center of a tunnel, but once the tunnel curves or shifts and a visitor finds herself closer to one wall than the other, she’s headed for an embarrassing tumble. The streams and rivers of Pandemonium often follow such rules of movement, spiralling around tunnels or streaming through the middle. Even when interrupted, such streams mysteriously go back to their original courses, even if inertia and the objective gravity of the realm would dictate differently.
Optional Rule: Mad Winds
A constant strong wind screams through the echoing caverns, imposing disadvantage on Wisdom (Perception) checks that rely on hearing as well as on ranged weapon attacks. In Wintervault, the ice and snow also imposes disadvantage on Wisdom (Perception) checks based on vision, and after each hour that a creature is exposed to the cold winds, that creature must make a DC 10 Constitution save or gain a level of exhaustion; a creature that has resistance or immunity to cold damage automatically succeeds on this saving throw, as does anyone in protective cold-weather gear or any creature that is adapted to cold environments. The wind extinguishes all open flames and disperses fog and other clouds. A flying creature in the wind must land at the end of its turn or fall.
Communication in the winds is a trial; speech can only be heard by shouting, and even then only out to a range of about 10 feet.
Each hour that a character spends exposed to the winds, she must make a DC 10 Wisdom check or gain a level of exhaustion. These levels of exhaustion represent increasing levels of trauma and confusion, not physical exhaustion (disorientation at exhaustion 2, delusions at 3, self-harm and failure to care for oneself at 4, fugue and gibbering at 5). At level 6, the character’s mind snaps completely and the character gains an indefinite madness effect; confer with your player to select one, or determine one randomly
1 “I drink to forget.”
2 “I don’t like the way everyone is constantly judging me.”
3 “You’re all out to get me.”
4 “I believe that things are being kept from us at the highest levels that it’s all a [select a race] conspiracy. Why can no one see this but me?”
5 “I lie compulsively; I cannot bear for anyone to find out the truth abou me.”
6 “I hear voices that accuse me of (or entice me to do) terrible things.”
7-8 “I have developed a taste for killing.”
Deaf creatures automatically make their saving throw against this effect, as do creatures with resistance or immunity to psychic damage. A madness effect can be suppressed or healed as noted on page 260 of the Dungeon Master’s Guide.
Each hour that a character spends exposed to the noise of Pandemonium, she must make a DC 10 Constitution saving throw. On a failure, she is deafened for 1 hour. She may repeat this saving throw after each full minute to end this effect on herself. If she rolls a “1” on the initual saving throw, however, she is deafened permanently, or until a healing spell such as lesser restoration alleviates the condition.
In the Harmonica, all creatures have disadvantage on these saving throws.
Pandemonium is divided into four rough “levels,” based on their physical properties. The “uppermost” level into which most astral travelers enter is Pandesmos and is exemplified by massive “natural” caverns, some large enough to house a city or a nation. Here a group of well-meaning but nihilistic philosophers maintain The Madhouse; they do not seek to heal the sick here (a losing battle in Pandemonium) but rather to keep them comfortable, more or less. A traveler here can also find Wintervault, a series of icy caverns ruled by a fierce tribe of frost giant slavers. At the edge of this frosty domain is the city of Keener’s Wall, partially protected from the winds by its high walls and erected around a temple of Erathis. The banished of Keener’s Wall subsist among other things by trading with the giants.
The second level, Cocytus, is strange, because its tunnels and chambers appear to be worked by hand; the walls are often smoothed and leveled, and the tunnels smoothed off, but no one knows who would have accomplished such a feat. In the center of Cocytus stands a mountainous spire of rubble known as The Howler’s Crag. Legend has it that any message shouted from the apex of the crag will be picked up by the winds of Pandemonium and carried across the planes to the ears of its intended target. Deeper in the realm is the Harmonica, a cavern of carved holes, tubes, and chisels through which the winds play; the noise here is worse than anywhere else on the plane. Rumor has it that one who listens here for long enough will learn some forbidden secret of the planes, but if anyone has ever uncovered that secret, it is seems to everyone else to be indistinguishable from the rest of the madness of Pandemonium.
The third level, Phlegethon, lacks the subjective gravity of other pars of Pandemonium. Gravity pulls in a consistent direction, permitting more predictable flow of water, and the formation of stalactites, stalagmites, and other natural rock formations. Phlegethon stone also has the odd property of absorbing light and heat; this level of Pandemonium is completely dark and bitterly cold. The caverns and tunnels here are smaller even than those in Cocytus. Many of the banished of Phlegethon gather in Windglum, a town built in a cavern several miles wide and long.
Optional Rule: The Cold Dark of Phlegethon
Anyone in Phlegethon must make a DC 10 Constitution saving throw each hour or gain 1 level of exhaustion. Creatures who are adapted to cold-weather environments or who are dressed in cold-weather gear, and creatures with resistance or immunity to cold, automatically succeed on this saving throw. The frigid waters of Stygia are even worse; anyone immersed in the water for more than a number of minutes equal to its Constitution score must make a saving throw every minute thereafter instead of every hour, and most cold-weather gear provides no advantage.
Nonmagical light sources on Phlegethon shed light to only half their normal distance. When a character casts any spell that creates light, the caster must succeed on a DC 10 Charisma saving throw; on a success the spell is cast normally, but on a failure, the spell slot and action are expended, but the spell has no effect. All creatures in Phlegethon have advantage on saving throws against spells and effects that deal fire or radiant damage, and attack rolls for attacks that deal fire or radiant damage have disadvantage.
The “lowest” level of Pandemonium is known as Agathion. Here, subjective gravity reasserts itself, but the tunnels leading down from Phlegethon narrow down to nothing. Chambers and caverns here are isolated bubbles within the stone, connected to the rest of pandemonium only through planar portals and the like. Such chambers contain ancient secret treasure vaults, prisons for the most egregious offenders, and hidden lairs and redoubts. Many claim that the Tower of Vecna is located here, secreted in one if the secluded caverns, and that the god of secrets and his exalted reside within hidden pockets of Agathion, only pretending to be lost outsiders.
It is known that shortly after the defeat of the goddess Khala, her Primordial ally, Umbroras, the Lord of Rimefire assaulted Letherna, the Raven Queen’s domain in the Shadowfell, and that she staged a retreat that lured the titan and his forces through a portal into Pandemonium. Once there, she cleverly separated Umbroras from his army of dragons and giants, and trapped him in one of the vaults of Agathion, where his enraged bellows add to the many screams and howls of the plane’s winds.
The Boundary Isles of Pandemonium
Like the other dominions, Pandemonium has a massive, ocean-sized color pool, peppered with “islands,” mostly composed of the petrified fragments of primordial titans and gods that seem to have lodged in the color sea. Unlike other boundary islands, the isles of Pandemonium are sparsely populated. This is because (with the possible exception of Vecna’s followers, should the rumors be true) Pandemonium has no exalted. The outsiders of Pandemonium are not exalted of this realm who cannot enter it, but outsiders of other realms who instead awoke in Pandemonium.
Thus, the only inhabitants of Pandemonium’s border islands are those few fortunates who have found their ways out of the windswept depths. Such escapees are often hopelessly mad by the time they effect such an escape. Many of these escapees continue to flee, but others try to set up some kind of life on the isles. Sadly for these escapees, Pandemonium’s boundary lacks any protectors. Githyanki, agents of the Nine Hells, and other astral predators raid these islands regularly, capturing the banished as slaves or sacrifices