Builder's Manual · Chapter 1

Welcome, Builder

This project is the Mythras Imperative System Resource Document, imported as a working, browsable ruleset rather than a PDF. The Player's Handbook teaches someone how to sit down and play it. This manual is for you: how the project is put together, what each file type is for, and how to add to it without quietly breaking something three folders away.

The rule underneath everything here is ORC licensing. The bulk of what you are looking at — stat blocks, skill lists, spell effects, the game mechanics themselves — is Licensed Material you can use, adapt, and redistribute freely, provided you carry the attribution forward. A short list of things are Reserved Material instead: the names Mythras and Mythras Imperative (outside attribution), their logos, and the original artwork. Read <@Introduction.rule> before you publish a fork — it has the full ORC Notice and the attribution line to reuse. If you build a new setting on this chassis, your own world lore, factions, and characters are yours outright; you are not obligated to share anything beyond the mechanics you built on top of Licensed Material.

The shape of the project

Three kinds of file carry three different jobs, and mixing them up is the most common way a project gets confusing to extend:

Prose rules live in .rule.md files — markdown, no schema, no rendered layout. These are the sections a human reads start to finish: how skills work, how combat resolves, what a Wound does. They are long-form and discursive on purpose.
Structured compendium entries live in typed JSON files — .character.json, .skill.json, .spell.json, .power.json, .equipment.json, .creature.json, .vehicle.json, .location.json. Each type has a schema (what fields exist) and a generated layout (how they render). These are the things a table looks up mid-session: a specific weapon's damage, a specific creature's Move rate, a specific spell's traits.
Play-time-only files — game-start entries and gm-instructions files — are not reference material at all. They configure how a session begins or how the GM agent behaves once cameras roll. More on both in Locations, Starts, and GM Instructions.

The Player's Handbook explains procedures in the second person — you roll, you spend Luck, you pick a Combat Style. This manual explains structure in the first person plural — how a skill file is shaped, how a character references its skills, what happens if you add a new Characteristic. If you find yourself wanting to paste a rule from the handbook into this manual, stop: state what the builder needs to know to extend that rule instead, and link to the handbook chapter for the rule itself.

How to use this manual

Each of the following chapters covers one file type or one closely related group of types: what its schema is for, which fields are load-bearing versus decorative, and the convention that keeps new entries consistent with the ones already here. The last chapter, Extending the System, is the one to read before you introduce something genuinely new — a file type this SRD does not have yet, or a computed field where a manual one now sits.

A few things to keep in mind as you read the rest of this book:

Reference fields matter more than they look. A character's skills, powers, and inventory fields are not free text — they point at real skill, spell/power, and equipment files. Break that link (typo a slug, invent one) and the character sheet quietly shows nothing where a skill chip should be.
Folders are organisation, not enforcement. Nothing stops you from filing a new spell outside /Magic and Powers/Spells/, but every existing spell lives there, and a builder six months from now will look there first. Match the existing folder before you invent a new one.
Not every rule needs a schema field. Several types (creature, vehicle) deliberately keep their crunch in one big statBlock text field rather than dozens of numeric properties. That is a considered choice, covered in Creatures and Vehicles, not an oversight to fix.

Start with How the SRD Is Organized for the map of the whole thing, then jump to whichever file type you are about to touch.

Manual updated Jul 30, 2026.

Mythras Imperative

Trialeia and the Langesnachtkrieg

A complete Mythras Imperative campaign setting: a war-torn continent in the grip of a decades-long religious conflict, Trialeia's Long Night features pike-and-shot warfare, fractious Ecumenical and Halperian factions, mercenary companies, and the persistent ambiguity of whether the three prophesied Heralds — Conquest, Famine, and Pestilence — are metaphor, delusion, or something far worse.

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CreatedJul 30, 2026

UpdatedAug 18, 2026

The Long Night

A war-torn continent where faith is a weapon, mercy is a liability, and the Heralds may already be walking.

Trialeia is a continent scarred by the Langesnachtkrieg — the Long Night — a decades-long war between the Ecumenical faithful and the Halperian Reform, drawing in the Holy Legian Empire, Aubernia, Nordenskjold, Valastia, and a dozen smaller powers. The mythras Imperative rules engine drives the game: nine-step character creation, percentile skills, detailed combat with special effects, folk magic and superpowers, and a bestiary of creatures. The setting adds pike-and-shot era flavor, faction-driven political intrigue, and the open question of whether the three Heralds — Conquest, Famine, and Pestilence — are real or merely the stories desperate people tell themselves.

Author's note

Imported from the Mythras Imperative SRD text. Long prose sections are kept as markdown Rule files; skills, spells, superpowers, sample vehicles, and creatures are stored as structured records. Source text is reproduced as-is, including any typographical artefacts present in the original document.

Inside the World