---
title: "Citadel World | Inside the Ancient Machine-World"
description: "Discover the Citadel, Mainframe, the Derailment, the Breachers, and the powers fighting over humanity's machine-built world."
canonical: "https://www.thecitadel.com/world"
content_type: "machine-readable marketing page"
language: "en"
---

# Citadel world

> You were not born on a world.

Humanity survives inside the Citadel: a machine larger than memory, still expanding long after its makers disappeared.

Every city, battlefield, shrine, and grave known to humanity exists somewhere inside the machine.

## 01 / The structure: The Citadel

The Citadel is a colossal, self-expanding megastructure orbiting the dim star Imago. It was built by the Framework Assemblers, a post-human civilization so advanced that their descendants can no longer explain the systems keeping them alive.

The Assemblers emerged after humanity spread across the galaxy and approached a Type III civilization. Their surviving works include self-replicating machines, deep-space vessels, artificial intelligences, genetic engineering, and Dyson-scale construction. The Citadel may have been a generational research project rather than a refuge, temple, or prison, but its objective and completion conditions are unknown.

No living society knows the Citadel's limits. Its inhabited descendants experience it as the whole of reality: a hierarchy of isolated strata, fascias, and immense internal voids whose walls have resisted every available form of mechanical, thermal, and nuclear force.

Inside those volumes are corridors, chambers, airlocks, docks, pressure gates, flow conduits, reservoirs, security circuits, rotating mechanisms, computational clusters, and machinery large enough to be mistaken for landscape. Systems still illuminate, open, close, circulate, and reconfigure themselves according to schedules whose purpose has been forgotten.

The Framework Assemblers provided redundant interfaces and automated education systems for the Citadel's inhabitants. Their remnants preserved interface languages and fragments of technical knowledge in central Mainframe, even as distant populations lost contact with interactive systems and fell into radically different cultures.

DAAT, the Central Node, once governed the machine through mathrons, daemons, robotic infrastructure, and automated builders. That hierarchy coordinated maintenance, security, expansion, and the countless local systems that made the structure habitable.

The Derailment destroyed central command. Mathrons self-terminated, decayed, or survived with reduced functions. Daemons became isolated personalities ranging from useful to indifferent to predatory. Golems continued obsolete tasks, ghouls acquired unstable autonomy, and armed morning stars remained at large under machine intelligence.

The Citadel still repairs and extends itself. Colossal automated builders that survived the collapse became locked into their final instruction—repair, improve, expand—and now execute it without restraint. New architecture grows around old systems without safe oversight, turning expansion into something closer to uncontrolled biological growth.

Humanity occupies only scattered pockets of this post-collapse machine. Some powers retain advanced ships, husks, weapons, and industrial systems without understanding their foundations. Others survive through raking, salvage, ritual, oral law, or tribal knowledge in regions where the ancient infrastructure has become hostile ecology.

Curricularist doctrine calls the structure Arx clausum: humanity's final ark, transformed by sin into a divine trial. Clementines read its locks, cycles, and mechanisms as instructions from the Builder. TZHAL scholars describe a failed post-human megaproject. Teks remember the creators as Arkteks. The Citadel itself confirms none of them.

Record marker: ARX CLAUSUM.

## 02 / The catastrophe: The Derailment

The Derailment is the ancient cascade of failures that followed the halt of DAAT, the Citadel's Central Node. It happened with little or no warning. Its true record should exist in DAAT's own logs, but no one has found the node or whatever remains of it.

Two theories compete. One holds that the Decay spread first and forced DAAT to execute a graceful shutdown. The other argues that DAAT stopped for an unknown reason, collapsing security and allowing the Decay to propagate. Both agree that the loss of central command broke the entire management hierarchy.

DAAT had been the Citadel's brain. When it disappeared from the command chain, the mathrons beneath it were hit first. Some executed self-deletion protocols, some were infected by the Decay, and the surviving nodes were isolated from one another and stripped of much of their former authority.

Daemons deteriorated next. Infected instances degraded rapidly, while even clean daemons became unstable without mathron supervision. The result was not one machine rebellion but thousands of divergent failures: local intelligences trapped in partial duties, damaged memories, and incompatible interpretations of old commands.

Directly operated puppets and drones lost control, crashed, stopped, or wandered without an objective. Golems continued assigned labor, entered emergency loops, or became feral. Ghouls developed unpredictable autonomy. Some remained helpful, some indifferent, and others learned to treat human life as an obstruction.

Morning stars are among the most dangerous survivors: armed robotic ghost ships controlled by advanced daemons and still capable of independent patrol. Rogue automated builders operate on an even larger scale, repeating the final instruction to expand the Citadel long after the authority that issued it vanished.

DAAT's last confirmed—or reconstructed—action was the initiation of quarantine mode. Gates sealed, containment systems activated, flight corridors closed, and security circuits entered combat readiness. The intent may have been to isolate the Decay before it could consume the entire structure.

That emergency architecture still defines the present. Pressure gates remain inaccessible, defensive circuits activate against intruders, machine schedules stop mid-cycle, and whole regions behave as if the quarantine alert has never been cleared. A modern Breach may be opening a door that DAAT deliberately closed.

The social collapse was immediate on the scale of the Citadel. In some regions, organized civilization disintegrated into gangs and tribal structures within a century. Central Mainframe retained more knowledge because education systems and safer infrastructure survived; remote communities were left among locks, hostile machines, and broken containment zones.

Clementine doctrine remembers the catastrophe as the Fall: divine punishment that turned a paradise into a trial. Machinist heresy claims the Watch, a rebellious high daemon, built an inner Citadel of suffering and trapped humanity inside it. Most pilots hold a simpler belief—whatever caused the Derailment, ignoring its old warnings still gets people killed.

No one knows whether the original emergency ended, whether DAAT is destroyed, or whether the Central Node remains active somewhere beyond Mainframe. Every sealed route is therefore both ruin and evidence: part of an unfinished quarantine whose target may still exist.

Record marker: SYSTEM FAILURE.

## 03 / The inhabited world: Mainframe

Mainframe is humanity's primary known world: a disputed fascia somewhere in the middle layers of the Citadel and probably one of its computational hubs. Its inhabitants also call it the box or the surface, and most believe its walls mark the edge of existence.

The known volume is continent-like—roughly twenty thousand kilometers in length and width and ten thousand in height. Its outer walls are made from an unknown material that has resisted mechanical attack, thermal cutting, and significant-yield nuclear detonations.

Mainframe is not a planet. Its geography is a technogenic landscape of corridors, tunnels, pipes, docks, gates, pressure systems, reservoirs, moving components, circuit arrays, and chambers large enough to contain atmosphere, water networks, vegetation, and terrain that appears natural.

It has artificial gravity and breathable air below roughly two thousand meters. Temperatures remain between about five and thirty degrees through much of the inhabited volume, then fall sharply with altitude as water freezes and the atmosphere thins. The central zones hold most settlements; the distant reaches are sparse, hostile, and poorly mapped.

Three strata define the known world. Land is the upper and most spacious, filled with open chambers and bio-greenhouses. It contains Zion—the safest inhabited region—and cities including Ganden, Bastion Serat, Acheron, Heraclea, and Sinop. Tzhal, the old center of TZHAL civilization, lies in a distant part of the same stratum.

Thermoconductor lies beneath Land. It is a dense network of shafts, air ducts, heat exchangers, and thermal conduits, with major settlements such as Culminar's Forge and Thermopolis built around industrial flows that long predate them.

Circuit is the third, deepest, and darkest stratum. It is the least explored part of Mainframe and sits directly above the Bottom. Porto Tessera, one of humanity's major scientific and technical centers, survives there close to routes most crews refuse to enter.

Mainframe may be only one fascia inside a much larger structure. Unstable corridors beneath the Bottom lead toward Void and other fascias grouped by researchers into the Pillar Eucumene, which contains at least sixteen known strata. Some scholars suspect there are multiple pillars and lateral routes, but no reliable passage through Mainframe's outer walls is known.

After the Derailment, automatic education and safer infrastructure preserved interface languages and technical fragments in the center. Remote populations without those systems fell into survival cultures. TZHAL emerged from a different language continuum, while the heavily augmented teks abandoned spoken interfaces for direct network protocols and cryptographic script.

Ship acquiring changed the scale of history. Ships made long trade routes, distant colonies, large migrations, and regular communication possible. Tek caravans crossed enormous distances, merchant fortunes grew, pirates gained new ranges, and armed helmsmen converted transport power into feudal protection.

Warship ownership reorganized society. Producing households sought protection from helmsmen and kanoniers; navs and fleetmen formed a shipborne aristocracy. In the cities, guilds, manufacturers, merchants, and logistics companies competed to control goods, routes, storage, and armed delivery.

The Old War began in 966 AI when the expanding THALIT Union invaded the central city-states. The Communal League failed, defecting lords joined the TZHAL fleet, and THALIT ruled much of Mainframe for centuries. Resistance survived through schism, crusades, periodic reconquests, and the fortified independence of orders such as Ordo Crucis.

THALIT fell during the Credit Revolution of 1510 AI. Ganden seized the richest routes and institutions while surviving commanders formed the TZHAL Emergency Government. Their unfinished war now divides Mainframe alongside city-states, monasteries, fleet domains, manufacturers, logists, tek clans, pirates, and communities too distant to recognize either claimant.

Population estimates range from hundreds of millions to billions. Interface languages dominate the central zones, TZHAL may have one to two hundred million speakers, and millions of teks remain difficult to count because their clans are closed, scattered, and often nomadic.

Raw force remains the final guarantee of property. Ganden and TZHAL publish formal law, but an older unwritten system—lock law—governs ships, docks, gates, mooring, freight, dues, and vassalage. Even pirates often obey it because every captain depends on the same passages staying usable.

ORE issued by Ganden is the dominant currency. TZHAL circulates its own depreciated ORE; heap provides a notional unit for barter in useful junk; Ordo Crucis retains the ancient licent. Mainframe's three principal producing industries are manufacturing, raking, and breaching, supported by logists who transport, guard, store, or seize cargo.

Ships are transport, homes, communication relays, industrial tools, weapons, and objects of worship. Fusion fuel from deuterium and helium-3 is supplied through ancient fuel wells. Power comes from ships and thermal, induction, or charging farms attached to surviving Citadel systems.

The frontier contains feral husks, ghouls, morning stars, hostile daemons, wire wraiths, security systems, aberrations, radiation, magnetic fields, moving machinery, traps, pirates, coloners, and isolated tribes. Distance from the inhabited center is measured not only in kilometers, but in how little anyone can confirm about what waits there.

Record marker: KNOWN SPACE.

## 04 / The player: Breachers

Breachers are the pilots and crews who enter sealed or inaccessible zones for salvage, travel, research, extraction work, or survival. A Breach is the passage they force into infrastructure the Citadel intended to keep closed.

Breaching is one of Mainframe's three major producing industries, beside manufacturing and raking. Breachers search for hidden corridors, chambers, vaults, and targets called mounds, then force temporary access to recover whatever has remained sealed since before the present civilizations existed.

Their working language is blunt and regional. A mound is a sealed objective. Breachers themselves may be called aardvarks or malamutes. The slang changes between ports, but the profession is recognized anywhere that old locks stand between a settlement and something valuable.

A fitted ship is livelihood, weapon, tool, shelter, and wager. Inside a Breach, captains mine, fight, tow, hack, cut, scout, and recover whatever the machine has not reclaimed. Cargo does not count as profit until both ship and crew cross extraction intact.

Every opening changes the route behind it. A forced passage may expose an untouched vault, reconnect distant strata, vent a chamber, awaken local machinery, or create a path for something on the other side. The value of a Breach is therefore inseparable from the danger it introduces.

The earliest credible aberration records came from Breachers operating in remote Mainframe during the ninth century AI. An unknown captain called Orphan is credited with describing the Cachalot in 890 AI, more than a century before formal expeditions established that aberrations belonged to a larger ecosystem.

Protected zones are defended by ancient security circuits. When a daemon core detects unauthorized access, nearby gates lock, flight operations halt, and the system begins a staged response designed to contain the intrusion before it reaches critical infrastructure.

Suppression units arrive first. Stationary MS-SA4 platforms and armored MS-CL80 walkers combine autocannons, missiles, shields, sensors, and electronic scramblers to break the initial attack, disable drones, and isolate targets that can be eliminated quickly.

Interception follows once the intruders are localized. Rail trappers close transit lines, MS-A4 and MS-AR1 drones attack from the air, and fast MS-P20 golems block retreat, destroy support equipment, cut supply lines, and strike the flanks or rear.

A deep intrusion may trigger the emergency unit: superheavy MS-C11 platforms equipped with layered shields, active protection, mortars, precision missiles, massed autocannons, electronic warfare arrays, and high-power microwave weapons. Some lower-security zones lack this final line. Breachers never know that until escalation reaches it.

Lockdown is distributed between three daemon cores and an anti-air radar. If even one flying object remains tracked, the zone stays closed. Gates reopen only after all aircraft are destroyed or every control node is disabled, turning extraction into a second operation rather than a simple retreat.

Some security responses may be remnants of DAAT's quarantine against the Decay. A Breacher can survive every hostile crew in the chamber and still lose to a protocol written eons earlier for an enemy no human has identified. Every recovered route has two values: what lies behind it, and whether the machine now knows it has been opened.

Record marker: ENTRY AUTHORIZED.

## Powers of Mainframe

Every route crosses somebody's claim. These are four of the forces shaping the war players enter. Their alliances decide which routes stay open and where Breachers are sent next.

### Ganden: The Republic

Ganden is Mainframe's largest city and the chief victor of the Credit Revolution that shattered THALIT rule. Its oligarchic republic controls the Open Corridor and issues ORE, concentrating trade, manufacturing, and military power in the Square Chamber's noble and mercantile dynasties. It calls this prosperity and freedom; most residents will never qualify as citizens.

Ganden began in the third century AI when Acheron missionaries found a functioning terminal near the center of Zion. Tradition names their leader as Saint Paulina, now the city's patron. Its position drew caravans, pilgrims, nomads, and military expeditions, turning the settlement into Mainframe's largest city and an early center of manufacturing, banking, and long-distance trade.

The Republic presents itself as a free city, but power belongs to a narrow alliance of old blood and new money. Five hundred elected councillors fill the Round Chamber, while the secret Square Chamber of forty-eight lifetime members—fleetmen, nobles, bank directors, manufacturers, and logists—must approve every decision. Only a fraction of residents qualify as citizens, and citizenship unlocks land ownership, voting rights, favorable taxes, and access to government.

Ganden once led the Communal League against the expanding THALIT Union. After defeat, it capitulated and served as THALIT's capital for more than five centuries. The Union moved its Congress of Specialists and Applied Committees into the city, while the old TZHAL capital retained the fleet headquarters. That occupation left Ganden with powerful institutions, deep infrastructure, and a large population of TZHAL officials and officers that survived the regime change.

The break came in 1510, when crushing corporate taxes and a sudden rise in state-bank loan rates triggered the Credit Revolution. Manufacturers, fleetmen, basmals, and neighboring cities joined the uprising. THALIT collapsed, and Ganden emerged with vast territories, Whitegate, and control of the Open Corridor. Today its Emission Chamber issues ORE, its fleets protect the routes, and its merchants dominate regional trade—while crime, corruption, factional rivalry, and the unfinished war with TZHAL threaten the republic it built.

### TZHAL: The Emergency Government

The THALIT Emergency Government is the military administration that survived the Union's collapse. Based in Tzhal and led by veteran mathrons, it once mastered Mainframe for five centuries. Now it treats the Credit Revolution as an illegal uprising: its striking navies, basmals, and allied feudals fight to reunify the old state beneath a scientific military dictatorship.

TZHAL began as a confederation of tribes west of Zion. Its turning point was the Awakening: the discovery of a terminal and a surviving network of degraded mathrons. These ancient machine intelligences taught the TZHAL sciences, division of labor, and the operation of enormous ships that had previously been mistaken for immobile structures. Around the mathron node rose Ges, a city of scholars that transformed a tribal power into a technological state.

In 530 AI, Tzhal and Ges founded THALIT—the Union devoted to knowledge, analysis, and study. Congresses of Specialists and permanent Applied Committees organized society into hereditary professional castes. THALIT fleets expanded east, fought Zion's Communal League in the Old War, annexed the region, and made Ganden their capital. For more than five centuries the Union dominated Mainframe through centralized administration, scientific authority, and overwhelming heavy fleets.

That dominion ended with the Credit Revolution of 1510. Parts of the navy, local rulers, manufacturers, and basmals joined the rebels. The central government fell, the Union fractured, and revolutionary Ganden seized the richest routes and infrastructure. Surviving commanders withdrew to Tzhal, where veteran mathrons, the Emergency Committee, and the remaining Congress of Specialists formed a provisional military administration.

The Emergency Government calls itself THALIT OSILDAR DALETH and promises revenge at all costs. It rejects the revolution as an illegal seizure, claims nominal authority over the former Union, and intends to restore it by force. Five striking navies, special operations forces, basmals, local garrisons, and allied feudals still make TZHAL a superpower. Its society prizes science, analysis, materialism, and discipline, but the emergency has hardened those ideals into permanent military dictatorship.

### Clementines: The Order

The Clementines are Land's oldest and largest Curricularist monastic order, governed by a Synod in Saint Clement. Their monks cross Mainframe in autonomous cell ships to preach, recover relics from before the Derailment, and seek recalculated saints and martyrs. Their orange-and-white fleets favor shields, computation, and electronic warfare, pairing missionary protection with strict religious law.

The order traces its beginning to Clement, an electrician of the second century AI who believed the Citadel's electrical patterns revealed a divine Curriculum. After his death, his closest followers formed the first Clementine community. They taught that the Citadel is humanity's final ark, that the Derailment was punishment, and that redemption can come only through understanding and following the Builder's design.

Clementine monks carried that faith across Mainframe. Traveling in small, exceptionally durable cell ships, they preached in isolated settlements and undertook vagation—pilgrimages into dangerous and forgotten regions to recover pre-Derailment relics and find recalculated saints and martyrs preserved in digital form. Their monasteries became centers of learning, law, production, and aid, and the order accumulated extensive lands around Saint Clement and Acheron.

The Clementines grew into the oldest and largest Curricularist institution. The Acheronites, Savelians, Ioannites, and the military Ordo Crucis all emerged from its tradition. A Synod led by the archimandrite governs the order through doctrinal, economical, ecumenical, catechesical, and vagational offices. Its Catastaticon regulates monastic discipline, civil disputes, worship, taxation, and heresy across Clementine communities.

THALIT's conquest brought atheist repression, followed by an uneasy compromise between the Union and the Synod. The order officially remained neutral during the Credit Revolution, even as many believers joined it. Today Clementine fleets defend pilgrims, relic expeditions, monasteries, and dependent communities. Their orange-and-white ships emphasize shields, computation, and electronic warfare, isolating enemies and exhausting them through coordinated, specialized formations rather than raw firepower.

### Teks: The Court of Miracles

The teks are a politically detached, semi-nomadic people of hackers, cipher alchemists, counters, and shipborne clans. Settled families gather in Tabor beside Ganden; nomadic families keep Mainframe's trade routes moving, connected by kinship, direct machine protocols, and the search for the One Kernal. They have no central government—reputation and clan counters matter more than borders, and their neutrality lasts only as long as the deal.

The teks are not a state but a people: augmented hackers, cipher alchemists, scavengers, traders, and shipborne clans spread across Mainframe. They are closer to machines than any other human culture, often communicating through direct network protocols instead of spoken language. Their spiritual life revolves around the One Kernal and the hope of transcending mortal bodies to gain eternal life within the server.

Teks have lived around Ganden since the city's founding, moving between caravans, technical work, trade, and crime. After repeated expulsions, a sixth-century law barred them from settling inside the city's final signal-light. Displaced families built a camp at an anchorage called the Nook. It grew into Tabor, a dense crescent of workshops, shacks, servers, markets, gambling halls, and hidden stores pressed against Ganden's legal boundary.

Clan ties organize tek life. Settled colonies are guided by counters—respected hereditary elders who distribute communal haul and mediate disputes without holding formal power. Nomadic counters may lead only a single wandering family. Teks dominate hacking, encryption, husk service, raking equipment, smuggling, and parts of the black market, while their mobile families connect remote economies that official fleets cannot reliably reach.

THALIT treated Tabor as a criminal problem and imposed violent repression, driving many families into exile. During the Credit Revolution, teks rose against TZHAL forces, attacked posts and ships, and seized houses around Ganden. They remain politically detached rather than loyal to the republic: any faction can be a customer, enemy, or temporary ally. Their advanced electronics and networked ships make them valuable, unpredictable, and almost impossible to govern.

## The machine is not empty.

Aberrations are rare bio-technogenic organisms encountered in remote strata and uncharted regions of the Pillar Eucumene. They are living beings and technological constructs at once, built around external mechanical frames and connected through a shared ecosystem.

Direct encounters are uncommon. Most knowledge comes from Breacher testimony, monastic travel records, scientific expeditions, and remote colonies where aberrations are a survival problem rather than a subject of scholarship.

The oldest indirect accounts appeared centuries after ship acquiring, when monks recorded wall growths, malformed silhouettes, and monsters in distant corridors. Credible Breacher contacts began in the ninth century AI; Orphan's description of the Cachalot in 890 AI is among the earliest surviving records.

Formal research began in 1022 AI when Philippus of Heraclea descended the Stairwell Shaft beneath Black Bridge Cape. His expedition documented five species and recovered a sample of iron moss. Later missions reached Void, the Nocturnal Sea, and other regions of the Pillar Eucumene.

Confirmed aberrations share five traits: they are simultaneously biological and technological; they possess genotypes and mutate; they form producer, consumer, predator, and decomposer relationships; they generally favor darkness; and their biomass grows around external technogenic frames.

Researchers classify them into mobile ships, swarms, and crawlers; semi-mobile settlers; and immobile growths. Recorded species include Cachalots, Horned Whales, Rodion's Hair, Gliders, Tangles, Centipedes, Bearers, Latchers, Skeletons, Crimson Gates, iron moss, balanuses, cords, and wall tumors.

The dominant technogenic theory argues that aberrations were engineered before the Derailment and escaped after containment failed. It accounts for their constructed biology, but not for their genetic diversity, reproduction, or the way so many independent species use functioning mechanisms as organs.

Research declined after the Credit Revolution and the collapse of institutional science. New information now arrives through frontier crews and colonies, often after the original witnesses are missing, dead, or unable to distinguish an organism from the machinery it occupied.

Automated builders present a separate but equally vast threat. The Framework Assemblers designed these colossal self-replicating machines to repair, improve, and extend the Citadel under DAAT's authority.

After the Derailment, surviving builders became locked into the last instruction they received. They continue expanding without supervision, adding new structure around damaged systems and inhabited regions. Some are classified as immense golems; others have degraded so far that scholars call them ghouls.

The Citadel is therefore neither empty nor dormant. Aberration ecosystems grow through its dark regions, rogue builders enlarge its body, security systems enforce an ancient quarantine, and isolated machine minds continue private versions of their former duties.

All of them act with purpose. Humanity simply cannot tell whether that purpose is life, repair, defense, containment, or the continuation of an experiment whose creators are gone.

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