Case Mind: Detective Mystery

Quantara

About this game

A dozen hand-crafted murders, and new mysteries added as they are ready. One detective: you.

Case Mind is interactive detective fiction where you interrogate AI-controlled suspects, examine physical evidence, reconstruct the timeline, and make the final accusation — culprit, method, motive, and the proof to back it up.

WHAT MAKES IT DIFFERENT
Talk to suspects however you want. Ask about their alibi, press them on inconsistencies, calm them down, or confront them with evidence you've found — all in free text, no dialogue trees. Suspects respond in character, under pressure, sometimes lying.

But the AI can never cheat. Every fact, every piece of evidence, and the entire solution are locked in before you ever ask a question. The AI writes how a suspect responds — never what actually happened. Nothing is invented on the fly to trick you or bail you out.

THE INVESTIGATION BOARD
- Scene: the crime scene and every connected location
- Suspects: track stress, trust, and pressure as your questions land
- Evidence: a growing locker of clues, some obvious, some buried
- Timeline: reconstruct the night, beat by beat, as you uncover it
- Notes: your own detective notebook, plus auto-logged leads

MAKE THE ACCUSATION
Name the killer, the method, the motive, and the evidence that proves it. Get it wrong and the case stays open — but you've spent an attempt, and the clock is ticking. Get it right, and the full solution — and your rank on the leaderboard — is revealed.

THE DEDUCTION
No single clue names the killer. The angle of the blow tells you the hand that struck; the height tells you the build; a witness only ever glimpses a kind of thing, never a face. Each report rules out part of the household and settles nothing on its own — cross them on the deduction grid and exactly one name survives. Every clue is load-bearing: drop one and the case is no longer decidable. This is a logic puzzle wearing a trench coat, and the suspects lie about their alibis whether they are guilty or not.

AN OPEN-ENDED CASEBOOK
Twelve authored cases — from a locked library to a runaway train, a poisoned gala to a country-house nightcap — each an honest whodunit with a fair solution and clues that were always there. Plus fresh, fully solvable mysteries added to the casebook as they are ready.

PLAY IN YOUR LANGUAGE
Full support for English, Turkish, German, Spanish, French, Italian, Korean, Arabic, and Chinese — suspects even reply to you in your own language.

FREE TO START
The newest case is always free, in full, with unlimited questions — nothing is ever cut off mid-deduction. A subscription opens the whole casebook: every case in the archive and each new one as it lands. No ads, ever.

What’s new

Everything the game writes now reaches you in your own language. Case notebook entries, hints, verdicts and error messages were still partly English — they are translated throughout now, rendered per player rather than baked in. The sign-in screen is fully localized too, and Continue with Google finally carries Google's real mark instead of a stand-in.