#Josai Kobo-ki (城砦攻防記)

Contents

Index. This document is the entrance to fc12. It gives a single-glance guide to the scope and table of contents of the sourcebook, from castle-structure rulings to siege assault, defense, infiltration, and ruin exploration modes, and on to the sample castle.

Series specification: ../co/co-99-meta/co-99-03-fc-spec.md

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#One-Line Description

"Before a castle is a battlefield, it is terrain; before it is terrain, it is a promise that locks people inside."

This volume handles Sengoku-era Japanese castles and sieges through the zones, Domination, Breakthrough, Blockade, Defense, squads, and Core Zone rules of Honseyeong Yodam. Its core purpose is to make the same single castle usable from four perspectives: siege assault, defense, infiltration, and ruin exploration.

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#Meta Card

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#Core Principles

Let the reader understand the honmaru, ninomaru, sannomaru, castle gates, moats, earthworks, stone walls, watchtowers, storehouses, wells, mountain paths, and castle town in scene language.

1. A castle is explained first as background knowledge.

Connect each structure to existing rules such as zone, Domination, Defense, Breakthrough, Blockade, high ground, narrow path, wall/barricade, and Core Zone.

1. Then translate it into zone rules.

Instead of one enormous battle table, split it into scouting, interdiction, gate pressure, fire attack, night raid, negotiation, supply, Morale, inside contact, and Barrier destruction scenes.

1. A siege assault is not a large-scale war, but a bundle of scenes.

From the moment the gates close, food, wells, Popular Support, troops, the Barrier, the wounded, betrayal, and escape routes all become resources.

1. Castle defense is a game of choices while enduring.

Use defense patrol routes, gatekeepers, kitchens, wells, storehouses, shrines, drains, cliffs, and castle-town rumors as zone tools.

1. Infiltration is a scene that reads the castle's promises backward.

Handle collapsed walls, blocked gates, abandoned masterworks, earthbound spirits, yoma-tainted storehouses, and forgotten secret passages.

1. Ruin exploration is reading the zones left after the war is over.

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#Table of Contents

#00. Meta

• fc12-00-00-index.md — this document.
• fc12-00-01-about.md — sourcebook scope, zone conversion, four use modes, and the sample castle.

#01. Castle Background Knowledge

• fc12-01-01-castle-primer.md — basic structures and terms of Sengoku-era castles.
• fc12-01-02-terrain-and-approach.md — mountain castles, hilltop castles, flatland castles, rivers, lakes, moats, and castle towns.

#02. Zone and Structure Rulings

• fc12-02-01-zone-conversion.md — procedure for turning castle structures into zones/battlemaps.
• fc12-02-02-structures.md — castle gates, walls, moats, watchtowers, storehouses, wells, shrines, and secret passages.
• fc12-02-03-siege-hazards.md — fire attacks, falling rocks, collapse, smoke, rain, night, and Barriers.

#03. Siege Assault

• fc12-03-01-assault-guide.md — attacker preparation, scouting, pressure, and Breakthrough.
• fc12-03-02-siege-scenes.md — scene-based siege assault procedure.

#04. Castle Defense and Holdouts

• fc12-04-01-defense-guide.md — closing the gates, supply, Morale, Popular Support, and troop operation.
• fc12-04-02-holdout-clock.md — holdout clock and internal events.

#05. Infiltration

• fc12-05-01-infiltration-guide.md — infiltration routes, disguise, inside collaborators, and guard patrol routes.
• fc12-05-02-stealth-maps.md — example infiltration battlemaps with a castle background.

#06. Ruin Exploration

• fc12-06-01-ruin-exploration.md — ruined castles, postwar remains, and sealed castles.
• fc12-06-02-ruin-tables.md — ruin events and discovery tables.

#07. Sample Scenario

• fc12-07-01-kageyama-castle.md — Kageyama Castle basic setting.
• fc12-07-02-four-uses.md — four uses: siege assault, defense, infiltration, and ruin exploration.

#99. Reference

• fc12-99-01-quick-reference.md — quick reference for structures/zones/scenes.

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#Connections to Other Volumes

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#One-Line Invitation

"Before you knock on the castle gate, look at whom that gate is locking inside."