Districts
The Necropolis: A district of undead, policed by the Order of the Bone Shield, who are involved in capturing and punishing undead criminals and rogue mindless undead city-wide. Contains a gate to the Negative Energy plane, where rich undead build homes. Bodies from the rest of the city are sold to the Necropolis for labor and dietary needs of its citizenry.
Primordium: The seat of the city's ruling council, a pocket dimension in the original village from which the city was founded.
The Steamworks: A steam-powered industrial district. It is actually made up of a number of unconnected sites scattered throughout the city. Most of the city's technological advances, refined metals, and other manufactured objects come off of a Steamworks line. There is enormous conflict and strain between merchant managers and unions in the district. The steamworks hold gates to the elemental planes of both fire and water to allow for infinite steam power.
The Mage's District: A district set up by and for magic users. It has a gate to the astral plane, around which was constructed the Bazaar of the Bizarre. All manner of constructs and magical items come from this district. Those who need to commission a magical service need only come here to find it.
Customs and Immigration: A district that has a number of artificial gates which open to a variety of planar cities periodically to let in waves of new citizens. Potential citizens who aren't useful, who are impoverished, or who don't have a useful skill are turned away.
The Grove District: A district whose layers are made up of massive living trees. Rangers, druids, fey, treants, and other nature beings make their homes here. The Streetbuilders have to work almost constantly keeping the various groves navigable by walkways in the branches. The Groves export large amounts of fruit and edible fungi to the rest of the city.
The Draconic Heritage Collective: A district of beings with dragonic blood built around a temple dedicate to two ancient dragons (one red, one gold) within. The ancient dragons started a game of strategy against each other centuries ago. They have since become players of business and are the two richest individuals in the city.
The Commons: Not so much a true district as the place in between districts. Tends to house lots of housing with only a few shops or taverns. The suburbs of the city. Is policed by volunteer neighbourhood watches and the occasional M.I.
The Academy: A massive macro-school of all manner of higher learning. Mages, mechanists, and other scholars are trained here. Most move on to the district of their profession (the Mage's District and the Steamworks respectively for the listed examples) when they finish their training. Some, however, remain to study new concepts and make breakthroughs of their own. Such individuals lead a life of learning.
Lake District: A district of floating buildings with prime apartments and underwater communities for water-breathers. Is a massive source of fish and edible water-borne plants.
Stadel: A district which vanished suddenly and existed in a void for centuries. One day it returned as suddenly as it vanished, having apparently survived the void by the skill and guidance of the Stadel family. After returning, they fought a short battle with the rest of the city before being comforted. To this day they are largely isolationist and xenophobic.
The Vault: An extradimensional prison where convicted criminals serve their sentence. It is policed and wardoned by constructs. It is rumored that terribly magical experiments are perpetrated upon the people jailed for life.
Entertainment District: A district of theatres, musicians, artists, and performers. People go here for family-friendly and though provoking entertainment. They also go here to see people gutted by each other in gladiatorial fights. It's a very popular district.
Temple District: A district of temples, hospitals, and academies for paladins, clerics, and other clergy. People go here to worship and receive aid from their organizations. The temple district at large publicly denounces, and would have made war to if not for the law, the Necropolis. A portal to the positive energy plane exists here.
Mithral Heights: An elitist community of aerial races, airmen, and rich people built around a massive mithral tower. There are many floating islands and air docks that make up this community. They are policed by a privately hired force of magically-aided flying archers known as the Falcons.
Organizations
Cut-Throat Alliance: An organization that makes crime a business. Comprised of 80% of the organized criminals and 50% of the disorganized criminals in the entire city. Potentially the most powerful single organization, they have hidden teleportative gates throughout the city for their agents to use for a variety of purposes.
The Streetbuilders: A municipal organizations of builders, their primary purpose is to make sure layers don't collapse down on each other, an almost constant task. When they finish repairing everything, they're given a public building task. Most such buildings are unfinished when the Streetbuilders are called back to their repair work, and sit unfinished forever.
Cave Knockers: Keep the tunnels maintained and mapped, and make new tunnels. Sometimes required to fight unexpected threats in their line of work. The Streetbuilders of the caves.
The Eyes: A now illegal network of divination aided and amazingly skilled spies who keep track of everything going on in the city. Founded under a former regime, and since outlawed, they still report to the city's council, who do not publicly condone their actions. For the right price, they can provide amazing information.
The Holy Hands of Saint Merkiel: A coalition of healers who have set up hospitals in every district in the city. They publicly, vocally oppose the existence of the Necropolis and undead in general. They take no hostile actions, but offer euthanasia to any undead that enter, much to the dislike of the Necropolis's residents.
Humans First: Humans first is a speciest organization which exalts humans and wants all other races to get out. They hold that the original village was a human village, and therefore only humans deserve to be residents. They are often ignored, in spite of rumors that many policy-making officials are secretly members.
Civil Servants: A public bodyguard service for other public service organizations like the Streetbuilders. They are not a police force. Their sole task is to protect their charges.
Municipal Investigators: An organization to handle trans-district criminals, the Alliance, and other such criminals. They serve principally as investigators, and rarely perform arrests, but will do so if needed. They are called in on every Alliance-suspected crime.
The Collective: A communist pro-union organization in the Steamworks. The unions don't official endorse it. Its actions tend towards protest, sabotage, and even attack on the merchant managers.
The Wild: A neoprimitivist organization made up of druids, rangers, and other pro-nature organizations. Their long-term goal is to return the area covered by the city to a state of nature. They seek to break the seals around the Hunting Grounds and let nature do its work on the rest of the city.
Shadow Martyrs: Ex-Cuthroat Alliance members and other victims, the good guys in the dark.
Gatekeepers: An organization which is devoted to ending these mysterious raids on the city. Some stay behind to aid the police and guards, but most patrol the multiverse searching for the source of the attacks.
The Elemental Guard: Police force and defensive garrisons of the elemental colonies.
Other
Random Gates: Random gates will sometimes appear throughout the city for random amounts of time. Magical devices which provide a countdown for the gate's disappearance and devices which hold open the gates are (relatively) common.
Gate Raiders: Occasionally, bizarre or random-looking humanoids will spill out of a random gates, stealing, killing, and retreating back into the gate just as it closes. Those that are captured die shortly after the gate closes and, as such, current policy is to just kill them outright. No two look alike. Sometimes a marauding monster will spill out instead of raiders. People looking to get on the good side of local police are well-advised to put down such monsters - if and only if they have sufficient skill to.
Crystal Observatory: An observatory built in the Mithral Heights by professors from the Collected College. They are always looking for new, better crystals to use as lenses, and are willing to pay exorbitantly for them.
Copper Junkyards: The various scrapyards of the Steamworks. Poor tinkers and mechanist will go here for raw materials, and it is seen as the ultimate sign of the waste and corruption of cities by the Wild. Rust monsters tend to live here, much to the chagrin of anyone walking past with a particularly delicious piece of metal on their person.
Holy Ground: The holy graveyard in the temple district. They refuse to sell their dead to the necropolis, and therefore maintain this expensive burial ground with the tithes of their congregations.
The City Forge: The single largest forge in the city. The truly massive machines that the rest of the Steamworks often need for their jobs are forged here. It is staffed almost exclusively by tough, old, skilled mechanist dwarves.
The Sleeping Army: There is a cavern filled with this vast army, made long ago in a terrible conflict and put to rest, to be awoken in a time of need. They attack anyone with a weapon, but some hide among them unarmed.
The Block: This large and crowded apartment building has a peculiar habit of flickering about several districts, appearing in certain vacant lots in each in a semi-predictable pattern, slightly controlled by its inhabitants. Its tenants trade between districts and practice home industries to keep employed. It usually has a number of guests in it who wish to catch a ride to the next stop and see the world. A red light district built in a spiral pattern in one of the larger cavern networks of the city. The deeper down the spiral that a person goes, the more perverse and disturbing the wares offered becomes. Most people can't even bring themselves to walk all the way to the bottom. There are technically no layers in this district, as it is a spiral. People found to be committing a crime are captured and sold into slavery in this district until they pay off their debt.
Ravenshome: A district full of raven statues. Those that break major laws disappear. Those that break minor laws have their offenses appear in a tattoo on their arm, listed in over 100 languages. Those that conceal their tattoo feel pain, and concealing their offence is added to the tattoo as a crime. Those whose tattoos get too large disappear. Anywhere you go in the district, there is always at least one raven visible. The crime rate in this district is incredibly low, and people who grow up here almost always end up with some sort of mental or emotional issues.
Collected College: A sub-community of the Academy, its purpose is as a lab and research ground for professors and other people who make their own education their life instead of a career.
Ungul: A small community attached to one of the groves designed around the needs of four-legged creatures of the city. It was designed and built by centaurs, and it is still administered by them to this day.
Gulliver's Heights: A district built by and for the creatures of size large and larger of the city. It has stable clouds above it for cloud and storm giants. They mostly keep to themselves, but tend to keep cupboards or closets converted to (massive) guest rooms for any miniscule, medium or smaller guests. It is the largest district, if not the most heavily populated.
The Hunting Ground: A corporately sponsored hunting grounds for big game hunters and creatures that have a biological or psychological need to hunt. The Alliance smuggled in more dangerous creatures for bored hunters. Some of the creatures were too dangerous to successfully take down, and the grounds grew overrun with dangerous creatures. It was sealed off from the public, and grove rangers frequently make raids to try to regain control, gaining combat pay and a bonus based on the danger of creatures they take down. The Alliance still smuggles in skilled or stupid hunters and the Wild seeks to release the seals, allowing the dangerous creatures to return the city to a natural state.
The Dark City: A former drow citadel annexed after a bloody conflict in the deepest levels of the mines. The Dark Army of city-loyal drow still besiege the castle of the Queen they betrayed when she attempted to fall back to her stronghold and leave her people to be conquered. Contains housing for the deepest miners, lodging for the Dark Army, and a large branch of the Steamworks.
Everdark/Shadowgate: Either two distrcits or a single one in which Shadowgate is a neighborhood. Everdark is a lightless place for nocturnal and darksighted creatures who don;t want to see the light. Shadowgate has spontaneous portals to the Shadow Plane and is beloved by casters of mysteries.
Galdren: The great fields that stretch as far the eye can see, a source of food for the city. They are run by small collectives which send representatives to central council for wider infrastructure planning. skill sharing, discussion, and electing a representative to the city.
Redmere: A district on the other side of the gates to the Plane of Fire. Trades with the denizens.
Aquarene: District on the Plane of Water, exports riverine and natural resources.
Aerodyne: District on the Plane of Air, a trade hub.