#A Realm in Four Branches — Between the Sengoku and Edo, the Four Forks of a Sealed World
Contents
Scope declaration / opt-in. This issue is a Variant of
co-99-01— a bridge setting·fiction that connects the faction map of CO (Sengoku) with that of EX3 (Chronicles of Edo), and whether or not it is adopted it has no effect whatsoever on theco·ex3baseline. The true history (正史) and the three IF branches (IF-A·IF-B·IF-C) are all narratives laid atop the factions and timeline of the canonicalco; wherever the facts conflict, the canonicalcoalways takes precedence.It creates no new ability score, no new check formula, and no new numeric data. This issue is pure narrative·setting — the factions·figures·events that appear all unfold only atop the canonical facts of
co-02-03·co-02-06·ex3, and the data (stats·checks) of frames·Artifacts·factions are not reprinted but referenced only by link tozn13·co.The true history too is only one branch. Exactly as in the drift principle of
fc10— the true history (Sekigahara→shogun→the Siege of Osaka→Tokugawa's unification→the shogunate's system for managing the great yoma) and EX3 are immutable canon, but the three IFs are separate world-lines that diverge from that true history. Which branch to bring to the table is left to the GM's choice, and this issue does not alter the true-history·EX3 canon.
#Brief — What This Issue Is
On the bridge that crosses from the Sengoku into the Edo hang one true history and three what-ifs.
Between Konsei Reiyotan's Sengoku dark fantasy (co) and the peaceful chronicles of Edo (ex3) there is a single bridge. Past Sekigahara and the Siege of Osaka, Tokugawa unifies the realm and the shogunate builds its system for managing "the Gate of the Spirit Realm" through administration and concealment — that one generation of transition. On this bridge, why did the Kagura Domain (神樂藩, co-02-03), which had been the greatest military power against the great yoma, not covet the realm but instead withdraw into the role of the great yoma's warden? This issue begins from that one question.
And to that question it offers four answers. One is what actually happened (the true history); three are the branches of "what if it had let go then" (the IFs). The true history is the road on which the Kagura Domain sheathed its own sword and became the shield that seals the yoma; the three IFs each depict what happens if the sword (the warrior houses) covets the realm, if the yoma grip the realm from behind, and if the sun (the solar deity) rises again into politics. All four branches are pure narrative, and there is not a single new rule.
The issue is composed as follows (the 7 documents after this front).
- The Kagura Domain and the Gate — The question: why did the Kagura Domain, the greatest military power against the great yoma, withdraw into being the great yoma's warden rather than unifying the realm / the 3 ages of the Spirit Realm and the bridge between them. (
01) - The Sealed Realm (正史) — The true history: the Kagura Domain's choice to seal → the true-history unification → the prototype of the shogunate's system for managing the great yoma · the dual chronology · three PC lenses. (
02) - IF-A: If the Sword Covets the Realm — The hegemony (覇) of the warrior houses (武家), the monopoly on sealing techniques, a realm built upon a sword's edge · three PC lenses. (
03) - IF-B: If the Yoma Grip the Realm — A puppet realm steered from behind by the yoma · three PC lenses. (
04) - IF-C: If the Sun Rises Again — The divine might (神威) of the imperial power (皇權) and the theocratic (神政) order of the Three Houses (三家) · three PC lenses. (
05) - Factions and Handles — A four-branch faction comparison table · common handles·stages · integrated scenario hooks (stats by link reference). (
06) - End Fiction — The single moment that forks before the Gate (pure Scent, Gravity ★★). (
99)
#Commentary — The Thesis in One Line
Thesis. On the bridge that crosses from the Sengoku into the Edo there is one true history and three what-ifs — and what decides that fork is always one person's hand.
"The Gate of the Spirit Realm" has never once been closed (ex3-02-01). In the Heian era it stood faintly open here and there; in the Sengoku it was thrown wide by war and blood; Edo merely pasted paper over that gap in the door and stamped it with an official seal. The true history is the tale of the Kagura Domain choosing that "paper and seal" for itself. But so long as the Gate stands open, the bridge forks into four branches depending on whether the one who stands before it withdraws or seizes — sheathe the sword and it is the true history; grip the sword and it is the hegemony of the warrior houses; hand yourself over to what lies beyond the Gate and it is the yoma behind the throne; raise a god again above the Gate and it is the divine might of the imperial power.
The four branches are equal fiction. The true history is merely the most likely path; none of them makes the other three "true." Which hand to depict is the GM's to decide.
#Meta Card
| Item | Value |
|---|---|
| Series | zn (one-shot series) No. 14 |
| Title | A Realm in Four Branches — Between the Sengoku and Edo, the Four Forks of a Sealed World |
| Nature | A CO (Sengoku)↔EX3 (Edo) bridge setting·fiction · true history (正史) + IF-A + IF-B + IF-C, four branches (pure narrative, 0 new rules·numbers) |
| Branches | True history = canon-adjacent fiction / IF-A·IF-B·IF-C = non-canon fiction (all four equal; none replaces the co true history) |
| Volume | 8 documents (front + true history 1 + IFs 3 + factions·hooks 1 + end fiction) · reading time about 12 minutes |
| Blocks (whole issue) | Brief · Commentary · Scent · Table · Note (this front document itself is Brief · Commentary · Scent) |
| Authority | Reference Only (setting commentary) + Fiction-Only (4 narrative branches) + Summary (Table). No new ability score·no new check |
| Dependencies | co-99-01 authority (Variant) · co-02-03 factions · co-02-06 timeline · ex3 Edo era · fc10 drift principle · zn13 Legendary Godframes (data reference) |
| Main-line version required | co >= 1.2 |
| Current version | v1.5 (zn14-VERSION) |
#Contents
Below are the blocks of each sub-document (this front document itself is Brief·Commentary·Scent).
| Document | Type | Content |
|---|---|---|
00 front | Brief · Commentary · Scent | Scope declaration · meta card · contents · production/AI notice · Scent |
01 The Kagura Domain and the Gate | Brief · Commentary · Scent | The question: why did the Kagura Domain, the greatest military power against the great yoma, withdraw into being the great yoma's warden rather than unifying / the 3 ages of the Spirit Realm and the bridge |
02 The Sealed Realm (正史) | Brief · Commentary · Scent · Table · Note | True history: Kagura Domain seals → true-history unification → prototype of the shogunate's management system · dual chronology · three PC lenses |
03 IF-A: If the Sword Covets the Realm | Brief · Commentary · Scent · Table · Note | IF-A: warrior-house hegemony · sealing monopoly · a realm on a sword's edge · three PC lenses |
04 IF-B: If the Yoma Grip the Realm | Brief · Commentary · Scent · Table · Note | IF-B: yoma behind the throne · puppet realm · three PC lenses |
05 IF-C: If the Sun Rises Again | Brief · Commentary · Scent · Table · Note | IF-C: imperial divine might · the Three Houses' theocratic order · three PC lenses |
06 Factions and Handles | Table · Note | Four-branch faction comparison table · common handles·stages · integrated scenario hooks (stats by link reference) |
99 End Fiction | Scent | The single moment that forks before the Gate — one breath in which the true history and the three what-ifs diverge (pure Scent, Gravity ★★) |
Reading order: front → 01 (the question) → 02 (true history) → 03–05 (the three IFs) → 06 (factions·hooks) → 99 (fiction). The heart of the table is 02's dual chronology + the fork of the three IFs in 03–05 + the comparison table·hooks in 06.
End fiction. A pure-Scent story is carried at the end of this issue —
99. Its Gravity is ★★ (the weight of an era's turning — it depicts not spectacle but the tension of a single moment in which "one person's hand before the Gate divides the realm").
#Production Notice
This issue is No. 14 of Konsei Reiyotan's zn (one-shot) series. The conceit of a bridge connecting CO (Sengoku) and EX3 (Edo) rests on the canonical grounds of the era's transition — the Sengoku→Edo passage of the co-02-06 timeline, the survival·extinction of the factions in co-02-03, and the "Edo afterimages of main-line factions" principle of ex3. This issue is pure narrative·setting, and it creates no new ability score, no new check formula, and no new numeric data. The four branches — true history·IF-A·IF-B·IF-C — are all Fiction-Only narrative and Reference Only commentary, and the factual relationships of the factions·figures·events that appear are always governed by co-02-03·co-02-06·ex3. None of the four branches replaces the co true history — the true history is a canon-adjacent retelling, and the three IFs are merely separate world-lines that diverge from the true history exactly as in the drift principle of fc10.
★ Canon↔new distinction. The Three Sacred Treasures·Amaterasu·the Arahitogami (現人神)·the Kagura Domain (神樂藩)·Konryu (混流)·Enma-doji (閻魔童子)·the Gate of the Spirit Realm and the like are actual canon (co-02-03·co-04-07-16·co-07-03·zn13-08 and so on) and use their original names. By contrast, the Return of the God (回神) (the returning-god event)·the Three-House (三家) Condominium·the Imperial House's Summoning Right·the Court's Rise to Power (朝廷)·the theocratic (神政) order are new narrative concepts for IF-C, marked "(new)" in the text. In particular, do not confuse the Return of the God with the Kaishin — the Return of the God (回神) is the event of divine might (神威) descending back into politics (new), while the Kaishin (改神) is the Legendary Godframe "Amaterasu-no-Kaishin (天照之改神)" of zn13-08 in which that event is made flesh through the Three Sacred Treasures (canon). That among the Three Sacred Treasures the mirror (Yata-no-Kagami) is not a Divine Artifact but a Masterwork (the asymmetric triad of co-07-03·zn13-08) is likewise honored as is.
#AI Use Notice
A substantial part of this material was produced with the help of generative AI (LLMs) in the course of planning, drafting, prose arrangement, and proofreading. The GPT Image 2 model was used in the image-generation process. This issue takes the Korean edition as its original, and Claude Code and Codex were used to produce the Japanese and English editions. Final editing and the responsibility for publication rest with the creator.
Should there be any changes in domestic or international law regarding AI-assisted works, the applicable law will be followed.
#Scent — One Sentence
"The Gate has never once been closed. Only the hand that stood before it chose a different realm each time — withdraw, and it is the true history; grip, and it is a what-if."