Intent: fair-solve AI murder mystery host

An AI murder mystery host that doesn’t rewrite the culprit

Chat-style AI DMs often invent a new killer when players press hard. RailMystery runs on a fixed-rail story graph: every clue, accusation, and ending stays on legal edges. The culprit is authored once — not improvised mid-session.

The problem

Open-ended AI hosts drift

When the model is free to invent, “who did it” can change after a clever question. Tables feel clever for five minutes, then unfair — and nobody trusts the ending.

Hard to re-run with friends

If the solution isn’t stable, you can’t recommend the same script twice. Hosts need a solvable case, not a new improvisation every night.

Our angle: fixed-rail, fair-solve

Culprit locked; AI narrates along legal edges only

Story graph authored ahead of time — killer, motives, and key reveals are fixed.
AI DM narrates and adjudicates only along allowed edges (no mid-game rewrite).
Private digital props stay on each guest’s phone — fair information asymmetry, not LLM invention.
First commercial English pack: Midnight Ferry.

How it works

Host buys one seat

Early Host $7 · Launch Pack $12 · Founding Host $15. One purchase unlocks the room.

Claim your host pass

Recover the pass on the claim page with purchase email + Gumroad order id.

Open a room; guests join free

Share a short room code. Guests play from mobile browsers — no app, no guest fee.

Ready for a fair-solve table?

See Early Host seats, guest-free join, and Midnight Ferry on the presale page.

View Early Host seats — $7 / $12 / $15

Or go deeper: host-pays / guests-free · Midnight Ferry script pack