City built inside mouth of huge funnel-shaped cavern. All the garbage of the city rolls down the slope of the funnel and into the caverns below. Out of the mouth of the funnel sprouts the Chanterelle, a giant diaphanous fungal 'tree' the exact colour of cherry blossom. It is edible, luminous and so tall that it grazes the cavern's high roof. At semi-regular intervals it weeps psychoactive spores over different parts of the city - this is the famous 'false weather', causing sharp unpredictable mood swings and periods of collective insanity that the locals have learned to live with. A couple of days after a sporefall, sterile baby mushrooms will begin to sprout from every surface. Without a male partner of the same species the Chanterelle cannot properly reproduce and the Mushrogun, who lives in an inverted Japanese castle built into a stalactite in the roof, will pay a fortune for one. Each neighbourhood of the city is controlled by a different daimyo and they all war endlessly over territory. The symbiotic fungal armour of their samurai infects the bloodstream of anyone who wears it.
2. CITY OF THIEVES.
Anthill slum of dark corners, twisting passages and secret doors. Smells awful. Like every basement, sewer, dive bar and homeless encampment in the world all crammed together. No distinction made between public and private space. Everyone sleeps on the floor, wears rags and mutters. Seems abandoned until you find the gate to the Dark Market, inside a cave that bulges like a cow's stomach, where junk merchants in black silk tents claim to sell everything that's ever been stolen in the world. Founded by the thief who stole fire from the gods - she fled into the Veins to escape thunderbolts and liver-pecking eagles. Illuminated by hooded lanterns that contain embers from that eternal flame. The thieves may seem miserable but they're bound together by criminal solidarity - they steal from each other so casually that all property is essentially held in common. Anyone who can keep up with their constant pickpocketing is welcomed into the fold. It's taken for granted that anyone who walks through the city is constantly robbing and being robbed - travellers with thief levels swap all their treasure with random other treasure, travellers without leave empty-handed. The city is much richer than it looks - it thrives on robbing other Veins communities, to their endless chagrin, though it never steals enough to drive its victims to starvation.
Inhabited mining complex beneath a mountain range of guano. Nobody has ever seen the giant bats who presumably roost in the caverns overhead. The guano is rigid enough to form solid ceilings and the smell is surprisingly mild, almost unnoticable after a few days. It makes excellent fertiliser for fungal crops and is home to a thousand species of roach, worm, centipede and beetle, each more delicious than the last. Fire is banned, since the guano is explosive, so most food is eaten raw. The citizens have learned to navigate by echolocation, constantly clicking under their breath. They have huge texturally-complex Gothic cathedrals, barely visible by glow-worm light, and a kind of Noh-like silent gesture theatre. The dark debating chamber of their parliament hums with excitable clicks and hisses.
4. CITY OF THE BLACK WAVE.
Set in the overhang of a frozen tsumani of stone. A bright river of lava cascades over the top and drains away into a burning lake. Pilgrims to the city must duck through the the occasional gaps in the molten curtain, hoping it doesn't come down on their heads. Invading armies are fucked. The black stone is very hard to tunnel through. The proudly-isolationist city is home to all manner of exiles and political refugees, who complain endlessly about the heat and the water rationing. It's infested with tiny adorable house salamanders who chirp like geckoes and spit hot ash. It allows the practice of free religion and its Avenue of the Gods holds the shrines of thousands of jostling microcults, most of which would be banned almost anywhere else. It eats fruit from the white vines that grow up the side of the wave but must import most other food.
5. THE PARASITE TWINS.
A bottomless, echoing ravine with a city built into each wall. The cities hate each other and are constantly at war. The best way to catch the formless pale jelly-things that haunt the air of the ravine, sifting the air for food particles that drift down from some functioning ecology thousands of miles above, is to throw a spider-net from one wall to the other. This requires anchoring-points on both sides of the ravine, which means a constant struggle for territory. Where the ravine is narrow the cities use grappling hooks, crossbows, hooked polearms and javelins. Where it's wide they use batwinged gliders and catapults, hurling boulders hefty enough to dislodge entire neighbourhoods. They regard any suggestion that they ought to work together and forge an alliance with open contempt.
6. CITY OF BLIND PRETENDERS.
A cold stream running through a warren of soft, pitted limestone. Comfortable, smooth-cornered rooms like the cells of a well-funded monastery. After he was blinded, castrated, flogged and chased naked through his burning palace by a pack of wild dogs, the emperor Basiliscus II 'Kopronymos' found his way to a place of refuge beneath the earth. He survived on sluggish blind fish, unused to predators and easily caught with bare hands, and on a slow trickle of supplies from his loyalists on the surface. When those loyalists were caught, blinded and exiled, they followed him into the Veins. The city is small, really just a town. Every poor soul who lives there is descended from some overthrown aristocrat, and has some wild plot to gather an army and reclaim their ancestral title. Light is illegal and they blind their children at birth. Their alchemists are working on truly invisible fire. About a third of them are members of the Babunic Church, gnostic iconoclasts who believe the sensory world is a sinful delusion. They still sometimes get funding from above, though Basiliscus' empire fell long ago and was forgotten.
The treasure vault of some lost and ancient sovereign. Dunes of gold dust, plains of gold tiles, hills of coins, gilded valleys presided over by the impassive faces of huge golden sphinxes with jewelled eyes. Sparkling chandeliers hanging from bridges of gold chain over gold-rimmed canyons with walls of exquisite porcelain. Colour-coded mountains of emeralds and rubies. Landslides of boulder-sized pearls. Accessible only via a maze of tight, vertical passages that compels any climber to carry the absolute minimum amount of weight - even a single excess crumb can spell doom. Hungry villagers in gold-brick houses rely for their survival on a caste of expert traders who can, with immense effort, escape with a couple of coins, and return with small dark bricks of the densest and most nutritious food-paste they can find. Light is reflected into a warm yellow omnipresent glow.
8. TIAMAT'S FORGE.
Permanent thunderstorm inside a huge sparkling geode. Erratically illuminated by lightning bolts that leap between vast columns of rust-infused crystal. Intensely humid and choked with swirling mist from which blind, newborn monsters emerge, screaming in unearthly tongues and flailing their pale tentacles. They were never meant to live and their flesh is usually poisoned with heavy metals. Designed as a terraforming engine, possibly by Archaeans. Something went wrong and now it endlessly shits out impossible foetal life. Townsfolk live in fortified shacks hewn into the sides of crystals, hunting the monsters and painstakingly boiling the toxins out of their corpses. Like fugu chefs, they know exactly what organs to shave away.
Lightless village that may or may not be inside the bowels of a gigantic worm. If you bring heat or light, make too much noise or claim that the worm does not exist, the villagers quietly kill you before you can anger it. If you spend fifteen hours a day licking bacteria off the damp, spongy walls you can get just enough nutrients to survive.