Holy City

Biodata

Feature	Information
Name	Holy City (圣城), formally Holy City–Neunter (“Eternal City”)
Alias(es)	Nointena; Neuentena; Eternal City; Human Holy City
Species/Race	Human city-state
Affiliation	Human Faction
Occupation/Role	Human main city; center for Knight training, Destiny Space expeditions, steam technology, and human external exploration
Status	Active and under reconstruction following the Holy City War; its destroyed King-level Deed’s world authority was reclaimed by the Chaos Center, requiring a future reapplication 2092
First Appearance	30

Power Progression

Stage / Realm / Level	Chapter	Notes
Territory-level city-state	31	One of humanity’s three known territory-level city-states, built on massive Brass ore deposits and centered around Destiny Space.
Lower King-level sovereign domain	1472	The Great Demon Commander fused a Lower King-level Deed with the city; a white World Rules curtain formed around the city walls, restricting outsider entry.
King-level city	1646	Official designation enabled a basic teleportation network linking the Holy City to other basic cities on Earth.
Deed authority lost	2092	The city’s King-level Deed was destroyed during the Holy City War, and its authority returned to the Chaos Center.

Background / History

Before the discovery that high-purity Brass could repel Higher Lifeforms, humanity was nearly exterminated; fewer than one hundred million people—roughly 1% of humanity—survived. The Holy City was one of the fortified city-states established around major Brass deposits and Destiny Space. 31

Over two centuries before the Great Expedition, the death of Italos’s king coincided with the awakening of Abyssal Demons. European exiles gathered in Italos, drove out the local Abyssal Demons, and founded the Holy City. It later adopted a Council Monarchy: the king became a ceremonial figure, while the Council held practical authority. 801

The city was built above a vast natural metal vein. Its accessible copper reserves were largely exhausted after extensive mining, leaving materials recovered from Destiny Space as its principal source of copper. 30

City Structure

The surface city is a spire-like national city-state occupying roughly half of Italos. Its original interior reconstruction was known as the Three Divine Staircases plan, incorporating the Ares, Hermes, Artemis, Poseidon, and Apollo stairs. 42

Layer	Elevation	Major Areas
First Layer	—	Outer Wall Layer and Slums
Second Layer	200 m	Royal Knights Academy, commercial zone, noble residences, and small-to-medium associations
Third Layer	500 m	Royal Family, Church, Knight Order headquarters, and major associations
Fourth Layer	1,000 m	Former Supreme Council district 783
Post-Transformation Apex	1,500 m	The Column of Steam and Holy Ring, which rose beyond the former Council level 1470

Dark Side

The Dark Side is the vast underground city retained after early mining operations. The Supreme Council preserved half of the former mine and launched the Dark Side Plan as a long-term preservation measure. It houses the Hell Knight Order, Black Rose Knights, and Terminus Knight Order. 521

• Nearly a thousand Pillar Buildings support the surface city and serve as underground observation points. 522
• Low-rise construction and limited residency make the underground district easier to control. 522
• The Underground Forge Citadel supports the city’s industry, trains blacksmith apprentices, and functions as a military-industrial base. 271

Steam City

Steam City, also called the Heart of the Holy City, is an embedded city built into the second and third layers. It was conceived in Eternal Night Year 103 by first-generation Chief Engineer Gito Leslie and 219 construction engineers as the “Eternal Heart” project. 783

After eight years of revisions, the project expanded from an energy facility into a secret research city intended to supply the entire Holy City while advancing steam technology alongside Destiny-derived power. Steam Knight Order personnel were required to reside there, and mechanically gifted citizens could pursue the Mechanical Apprentice path without undergoing Destiny selection. 783

• Eternal Heart / Column of Steam — the city’s central power source, connected to Steam City through innumerable pipe networks. 783
• Artificial Intelligence and steam transport — Steam City employs mechanical intelligence, rail systems, steam locomotives, and Rust Whale metal airships. 783
• Security — entry requires strict identity verification, contamination screening, and, even for official Knights, an invitation letter. 783
• Patron — the Steam Knight Order’s Grand Commander is inseparable from Steam City’s economy and operation. 784
• Congreve Newton — Vice Commander of the Steam Knight Order and founder of the Mechanical God Cult; manages and monitors Steam City from behind the scenes. 784

Holy Ring

The Holy Ring is a fortress-like structure encircling the Column of Steam. Originally the Mechanical God Cult’s sanctuary and the Steam Knight Order’s primary operational zone, it became the Holy City’s new political apex after the Great Transformation. 1470 1477

The Holy Ring replaced the former Council district as the principal site for major deliberations. Its elevation and placement were a condition demanded by Newton during the city’s reforms. 1477 1480

Administration and Society

The Holy City’s original government was a constitutional monarchy with a parliamentary system. Social class is determined not only by wealth, but also by ability and access to Destiny Space advancement. 42

Following the Great Expedition, the authority of the Thirteen Knight Orders surpassed that of the Council. The Great Demon Commander, Victor Diano, took the central position after obtaining the World Throne and the Lower King-level Deed. 1472

Knight System

The city’s Knight system was formally established eighteen years after the Holy City’s founding. Knight status grants the legal authority to leave the city, investigate external threats, and join a Knight Order. 521

• Royal Knights Academy — founded in Eternal Night Year 78; trains Destiny Space newcomers and improves Seed Breaking success rates. 521
• Knight Grand Selection — annual mid-October assessment for academy graduates who have achieved Seed Breaking. Successful candidates are assigned to suitable Knight Orders. 521
• Thirteen Knight Orders — the Holy City’s publicly known highest combat force; the Royal Family retains additional concealed forces for catastrophic emergencies. 797
• Royal Family / “Zero Knight Order” — originally composed of exceptional early Destiny Seekers; regarded as the First Knight Order before the modern Knight Order system. 801

Civil Security

Public security operates through multiple layers:

• Public Security Bureau — resolves ordinary civilian disputes. 68
• District churches and covert Knight intelligence stations — review incidents, support Knight-Errants, and occasionally station Knights within local churches. 68
• Investigation Missions — use preemptive prediction, investigation, and elimination to address possible Abyssal Demon births, portals, or heretic activity beyond the city. 730
• Writers — highly valued because their connection to Destiny Space can reveal portions of approaching danger, though their visions cannot precisely assess every risk. 158 730

Defenses and Strategic Assets

• Brass-based fortification — the city’s foundation was built around metal capable of repelling Higher Lifeforms. 31
• World Rules curtain — the Lower King-level Deed created a hemispherical barrier around the city; outsiders require the Great Demon Commander’s permission to enter unless they possess exceptional destructive power. 1472
• Zenith — a Steam Knight Order city-defense masterpiece made from Destiny Metal and powered by Endless Energy; it protected the city from a super-giant plant-covered meteorite. 1695
• Will of the Machine God — Newton’s technology links citywide mechanical components, prosthetics, and modified brains to the Patron, partially resisting Teacher’s mental invasion. 2062
• Holy City Blood Bank — during the Holy City War, the city distributed regenerative blood through its water sources while the Mechanical God Cult supplied prosthetics and recovery resources. 2083
• Mobile Sanctuary — a steam-powered cleansing church developed for the Great Expedition; it purifies Abyssal Demon corruption and supports the Holy Knight Order. 1400

Major Arcs

Event	Details
Creation of the Royal Knights Academy	The Academy was founded in Eternal Night Year 78 to train Knight-Errants before the Knight Grand Selection. 521
Eternal Heart Project	Steam City was planned as a hidden energy, manufacturing, and research city within the Holy City. 783
Eve of the Great Expedition	The Council, Knight Orders, Church, Royal Family, and Steam Knight Order coordinated a citywide expedition plan through an extended Council Hall meeting. 728
Great Expedition	A 3,280-person expeditionary force departed through Gayn Forest to occupy Milan before advancing toward London City. 803
Great Transformation	After the London Game, Steam City’s Column of Steam broke through the Council level, the Holy Ring became the new apex, and the city underwent widespread mechanization and military reforms. 1470 1471
Deed Fusion	The Great Demon Commander fused the Lower King-level Deed into the city, establishing the Holy City as a recognized sovereign domain. 1472
Exo-Planted Celestial Body Incident	A plant-covered meteorite destroyed roughly one-fifth of the city and damaged underground facilities, but the Deed barrier and Zenith prevented casualties. 1695
Holy City War	Teacher’s Didactic Influence and multiple Uncontrolled Ones threatened the city; the Holy City ultimately forced Teacher to surrender and remove his influence. 2062 2090
Post-War Reconstruction	Steam City deployed repair robots and Mechanical God Cult derivatives under the Patron’s Endless Energy, though damage from Malone’s final strike remained extensive. 2092

Key Affiliations

• Destiny Space — central to the Holy City’s survival, Knight cultivation, material acquisition, and inter-city communication. 30 31 1023
• Supreme Council — the city’s former highest legislative and executive body; its authority was later eclipsed by the Thirteen Knight Orders and Holy Ring. 557 1472
• Thirteen Knight Orders — provide the city’s principal public military power, external exploration force, and expeditionary command structure. 728 797
• Steam Knight Order / Mechanical God Cult — operates Steam City, develops core steam technology, and maintains crucial defenses and infrastructure. 728 784 2062
• Church and Holy Knight Order — conduct purification, spiritual supervision, morale support, and citywide religious functions. 728 1401
• Royal Family — ceremonial authority, symbol of strength, and holder of concealed emergency combat power. 797 801
• Dragon City — one of the other human main cities; generally maintains peaceful coexistence with the others. 1023
• Royal City — another human main city; relations are strained due to conflicting views on external exploration, Destiny Space, and the Great Expedition. 1023