Sealed Mystery
Blackfile №2: A Death at the Wyke Hydro
A speculator dies beside his nightcap in a snowbound spa hotel; the culprit was sealed before you play, and the AI cannot change the answer.
Blackfile №2: A Death at the Wyke Hydro is a free murder mystery you play inside ChatGPT, Claude, or Gemini. A snowbound 1929 poisoning whodunit: six suspects, one cup of hot milk, and a culprit sealed before you start. Solo, 60–90m a run. No signup and no app — open it in your assistant, or paste the play prompt anywhere else.
- Players
- 1
- Length
- 60–90m
- Rating
- 12+
- Version
- 1.1.0
Works with ChatGPT · Claude · Gemini. Free, no signup.
Opens your assistant with the game loaded. ChatGPT usually runs it straight away; Claude waits for you to press send. Same link on your phone as on your desktop. Playing in Gemini? Tap Copy the play prompt and paste it into a new chat. What works where.
No web access, or want it as an installed app?
The game card is the entire game — every scene, rule and answer, about 13k characters. Paste it when your assistant can't browse the web. The Skill installs Blackfile №2: A Death at the Wyke Hydro into Claude on any plan: download it, then turn on code execution under Settings → Capabilities and add it at Customize → Skills → + → Upload a skill.
How to start
- Open your AI. Start a new chat in ChatGPT, Claude, or Gemini. No paid plan required.
- Paste the case file. The file includes the sealed hash and boots the Wyke Hydro on the night Gerald Vane died.
- Investigate. Question the six snowbound suspects, search the rooms, and pin the cup's route from the kitchen to the reading room.
- Accuse and verify. Name the poisoner, the poison, and the reason — then open the seal and hash it yourself.
Questions
- How do you stop the AI from inventing the murderer at the end?
- Vane's killer, the poison, and the reason were written out and hashed with SHA-256 before the card shipped, and that hash is printed in the case file you paste. The AI can only reason from that fixed text — it cannot decide the poisoner is whoever you happen to suspect at hour two — and when you accuse, you can hash the reveal yourself and watch it match.
- Is the case actually solvable, or is it guesswork?
- It is solvable by deduction. Every suspect but one is cleared for the poisoning window by a witnessed alibi or a physical fact, and the remaining clues fix who had both the cup and the poison. Find the evidence, cross off the innocent, and one name is left.
- Do I need dice, an account, or any tools?
- No dice — this case turns on deduction, not rolls — and no account beyond the chat app you already use. Paste the case file into ChatGPT, Claude, or Gemini and the Hydro opens on the night Vane died. Checking the seal afterwards wants nothing but a SHA-256 tool, and your operating system ships one.
- How long is it, and can I stop partway?
- About an hour solo, up to ninety minutes if you question everyone. Say "save" at any point to print a save code, then paste it into a fresh chat with the case file to resume exactly where you left off.
- How is this different from Blackfile №1?
- Different house, different crime, different shape of proof. №1 is a disappearance from a bolted conservatory in a 1925 country house, with no body and no way out; №2 is a poisoning in a 1929 spa hotel with six suspects the blizzard has shut in and a witnessed alibi for all but one. Play them in either order — they share nothing but the seal.
12+ — a poisoning, and a reference to a suicide in the backstory.