Occam

The machine holds a secret rule. It will not tell you what it is. All it does is look at three stones you place in front of it, and answer one thing: accepted, or rejected. From that single bit of information — over and over — you work out the rule. WHAT YOU ACTUALLY DO Place three stones. Press TEST. Watch the machine's verdict. Every answer eliminates some of the possible rules, and every rule that could be the answer is listed in front of you, so you are never guessing blind. Then declare — and here is where it gets interesting. The earlier you declare, the higher your score. But you only have a few tests, a rival scientist is working on the same machine, and a wrong answer costs you the level. That is the whole game: are you sure enough yet, or are you being greedy? THE SKILL Most players start by testing what they think will pass. That is the wrong instinct. A good test is one that separates two competing rules — the answer teaches you something no matter which way it goes. Learning to think that way is the game. 100 HAND-BALANCED LEVELS Every level has been verified solvable within its budget, with no repeated answers. The difficulty grows by widening what a rule can be, not by hiding information from you. - Apprentice: generous tests, few possibilities, no rival - Machinist: stone size starts to matter — or is it a red herring? - Rivalry: four tests, and someone else is racing you - Master: compound rules, and every test counts BUILT TO BE FAIR - Every candidate rule is always visible. No guessing. - Every piece of evidence stays on screen. The game tests reasoning, not memory. - Get it wrong and you are shown a counterexample, not just a red X. - Colour-blind safe: every stone carries a distinct shape, not just a colour. ONE PURCHASE $0.99 unlocks all 100 levels. No ads. No in-app purchases. No account. Runs on your device. English and Vietnamese.