Ten walked in. The door sealed behind them.
Two objects in the mansion are cursed. Every night, the entity takes one researcher. Study the deaths, read your rivals, and name the cursed pair — or walk out the door and live with the not-knowing.
Chance is an illusion. With enough study, anything is solvable.
All ten researchers share that belief. The mansion will test it. There are no safe rooms, no jump scares, and no reflexes required — only evidence, patience, and the question of how long you dare to stay.
How a night unfolds
The game is a cycle of days and nights. Each night you survive is a point. Each death is a clue.
The morning meeting
Survivors gather. Some share honest suspicions, some bluff, some stay silent. The AI detectives remember how you behave — across games.
Pick a room
Choose where to sleep among twelve rooms of five objects each. Every room holds at least one cursed object. Nowhere is safe.
Night falls
The entity takes exactly one sleeper. Their room's objects go public, and one is confirmed not cursed. The dead teach the living.
Deduce — or leave
Narrow ninety-one possible pairs down to one. Then decide: another night of evidence, the walk to the front door, or the Confrontation.
Every morning, the same choice
Walk away
The door unlocks every morning. Leave with a point for every night you survived — and leave the mystery to the others.
1 point per nightStay another night
More nights mean more deaths, more confirmed-safe reveals, and a shorter suspect list. They also mean another draw from the entity.
Evidence accumulatesConfront
Seal a vote naming the cursed pair. Correct, and the case is solved for ten times your nights. Wrong, and no one in the room sees morning.
nights × 10 — or deathFourteen objects. Two are cursed.
Ninety-one possible pairs. A blind guess succeeds 1.1% of the time. A patient researcher does better.
- Mirror
- Candle
- Clock
- Book
- Bottle
- Chest
- Vase
- Locket
- Chandelier
- Hourglass
- Mask
- Rose
- Feather
- Crown
The cursed pair changes with every visit. Watch closely.
Why The Last Deduction?
Pure deduction
Evidence over reflexes: deaths, reveals, and failed Confrontations are your only clues.
Fair by construction: every case is solvable, and the AI rivals see exactly what you see.
Nine rivals worth reading
Named personas: sharers, hoarders, and bluffers who play to win — with or without you.
Grudges persist: honesty and betrayal at the morning meeting follow you into the next game.
The Bestiary
Thirteen entities: crowd hunters, lone stalkers, and worse — each biasing who is taken in the night.
Hidden until the end: the killer's identity is its own small deduction.
Beautifully scary
Dread, not shock: no jump scares, no strobing, no screen shake — the horror lives in slowness and absence.
Every effect has a dial: motion, light, atmosphere, sound, and haptics are all individually adjustable.
A career of cases
Quick Play is free: the full classic game, forever.
Detective Career: a one-time unlock adds a ladder of authored cases, ranks, tools, and tournaments.
Offline & private
100% offline: no accounts, no cloud, no tracking.
Procedural art: every mansion is drawn by code and seeded by your game — no two cases look alike.