English edition v1.3.3 · ex-doc

#Investigation, Kaidan, Cover-Up Cases

Contents

Investigation of a ghost story, empty alley corner, dropped hairpin, and a lantern with no writing, silence after a rumor.

Scene Tool. Turning Edo Kaidan into a playable investigation structure.


#Scent — The Night Rumors Become Evidence

A Kaidan is not a lie. It is evidence not yet admissible in court, and a truth that witnesses have retold to protect their own lives. Edo investigation follows, before any blood-stained blade, the people who tell the same story in different ways.

#Law — Investigation Structure

  • Divide investigation scenes into five axes: rumors, the scene, records, stakeholders, and spirit-realm traces.
  • Turn failed rolls not into dead ends but into false records, delayed intervention, or a witness in danger.
  • Let the resolution require choosing at least one of: eliminate, purify, negotiate, expose, or conceal.

#Scene Commentary — A Kaidan Is Not False Testimony

Running an Edo Kaidan investigation as a process of disproving rumors drains it of power. A Kaidan is not false testimony — it is a wrapping for truths people cannot speak directly. "A woman is crying at the well" might be a real onryo, the guilt of a family covering up a killing, or a name the Hundred-Tale Society has deliberately kept alive.

Investigation scenes come alive when the same story is told in multiple versions. Each witness saw something different; documents and rumors contradict each other; temple records deliberately leave blanks. A roll is not a button that delivers the answer — it is a tool for revealing why a given version exists.

The three layers needed for Kaidan investigation:

  • The story people believe.
  • The story the records tell.
  • The story the spirit-realm traces left behind.

#Session Application — Prepare Three Testimonies

  • First scene: the same incident is described differently by a witness, a record, and spirit-realm traces.
  • Complication: the Kaidan that makes the least sense is actually closest to the core truth.
  • Final question: do the PCs expose the Kaidan as fiction — or reveal why the Kaidan was necessary?

#Investigation Steps

  • Hear the rumor.
  • Find other versions of the same incident.
  • Watch who is spreading the story.
  • Decide whether to drive out the yoma, change its name, or resolve the grudge.

#Kaidan Are Ecology, Not Evidence

Edo Kaidan are not mere clues. A Kaidan is how yoma survive. People talk about the strange thing on the night road; storytellers refine it; theaters put it on stage; ukiyo-e give it a face. Through this process a yoma acquires a name, and the name collects fear.

The Hundred-Tale Society understands this flow. That is why they clash with the shogunate, which tries to erase Kaidan, and also with the Black-Tag Gang, which tries to treat Kaidan purely as merchandise.


#Investigation Structure

StageScene
RumorHear the first story at a bathhouse, tavern, nagaya, or theater back room
VariationCompare different versions of the same incident
SceneInvestigate a well, bridge, abandoned house, mansion, or warehouse
NameFind the yoma's name or the owner of the grudge
InterventionDetermine which of the shogunate, Hundred-Tale Society, or conspiratorial faction moved first
ResolutionChoose from: eliminate, seal, resolve the grudge, cut off the rumor, or make a deal

#Witnesses

In Kaidan investigation, a witness is both an information source and a danger. Intimidating a witness makes the rumor grow; the shogunate taking the witness away angers the Hundred-Tale Society; the Black-Tag Gang can sell the testimony.

Witnesses fall into these types.

WitnessUse
ChildSees the truth adults dismissed
PerformerTurns Kaidan into narratives
OkappikiScene information absent from official records
MerchantRemembers the movement of goods and people
HanyoReads traces from both the human side and the yoma side

#Resolution Is Not Only Elimination

Edo Kaidan don't have to end with a sword. Some onryo want a proper burial; some urban yoma want a name; some Hundred-Tale Society envoys negotiate with PCs to stop a human conspiratorial faction.

Combat is an important option, but not the only one. When a fight breaks out, rumors have already grown large enough — or someone has drawn a sword to keep the incident buried.


"An Edo Kaidan is the truth that couldn't become evidence, returning every night under a new name."