Sealed Mystery
Blackfile №1: The Vanishing at Larchmont Hall
An heiress vanishes from a bolted glass conservatory in a 1920s country house; the answer was sealed before you arrived, and the AI cannot change it.
- Players
- 1
- Length
- 60–90 min
- Rated
- 12+
- Version
- 1.1.0
- Updated
Works with ChatGPT · Claude · Gemini. Free, no signup.
Opens ChatGPT or Claude with the play prompt ready; press send if it hasn't started. Same link on your phone as on your desktop. Another app? Copy the play prompt into it, or, if it can't open links, copy the full game card below. What works where.
No web access, or want it as an installed app?
The game card is the entire game, about 13k characters: every scene and rule, and the answers the AI referees from. Paste it into an assistant that can't open links, without reading it first: it gives the game away. The Skill installs Blackfile №1: The Vanishing at Larchmont Hall into Claude on any plan: download it, then turn on code execution under Settings → Capabilities and add it at Customize → Skills → + → Upload a skill.
Blackfile №1: The Vanishing at Larchmont Hall is a 1925 country-house whodunit: an heiress bolts a glass conservatory from the inside and is not there when the doors come down. Solo, 60–90 min a run, free to play inside ChatGPT, Claude, or Gemini. No signup and nothing to install: open it in your assistant, paste the play prompt into another, or paste the whole card where links don't open.
How to start
- Open it in your AI. Tap Open in ChatGPT or Open in Claude, and press send, or paste the play prompt into any assistant that can open links. No paid plan required.
- The game loads. The case file carries the seal, a SHA-256 hash of the solution published before release, and opens on Larchmont Hall the night of the vanishing.
- Investigate. Question suspects, examine rooms, and follow the timeline. The AI answers only from the facts written in the case.
- Accuse and verify. Say "I accuse" and name who, how and why. The AI then reads out the sealed solution; paste the revealed answer into aigamecards.com/verify, which recomputes the hash in your browser.
Questions
- How do you stop the AI from making up the answer at the end?
- What became of Iris Larchmont, how she left a bolted glass room and why, was written out and hashed with SHA-256 before this card went public, and that hash is printed in the case file. The AI reasons from that fixed case and nothing else, so it cannot quietly settle on whichever suspect you have been circling all evening. When you accuse, you can paste the reveal into aigamecards.com/verify and hold it against the printed hash.
- Is anyone killed?
- No. Nobody dies in this case: an heiress disappears from a bolted room, and you work out how and why. It is a full mystery, with seven suspects, physical clues and one accusation; the 12+ rating is for a woman secretly dosed with a 'nerve tonic' and a coercive engagement.
- Can I solve it, or does the AI just tell me?
- You solve it. The AI plays the house, its suspects, servants, and physical clues, and answers what you investigate, but it will not hand you the culprit. Make your accusation when ready; the sealed file confirms whether you were right.
- What happens if I accuse the wrong person?
- You get one accusation and it stands. The seal opens either way: the AI reads out what became of Iris, and you score the clues you turned up, plus five for naming it right. If you are not ready to speak, say "save" instead: the case prints a code that carries your clues into a new chat with the case file.
12+ — no violence and no death; includes a woman covertly dosed with a 'nerve tonic' and a coercive betrothal.