ASSAY

You are the assayer of a candlelit royal mint. Every batch of coins that reaches your bench hides exactly one counterfeit — and the only instrument you're allowed is a brass balance scale with a strictly rationed number of weighings.

How to play

• Drag coins from the tray onto the left and right pans (touch works; keyboard too — select with the arrows or number keys, load with L/R, weigh with Enter).
• Press WEIGH and read the tilt. Every weighing is recorded in the ledger, and every weighing spends one of your brass weights.
• When you know — or when you're desperate — drag a coin onto the accusation block and stamp it. Right, and the round is yours. Wrong, and one of your three wax seals cracks.

The twist

The mint keeps your books for you: any coin your weighings have provably cleared gets stamped GENUINE automatically and can't be accused — but it can still sit on a pan as a known-good reference weight. No pencil-and-paper bookkeeping, just the actual deduction. Early batches tell you the forger's alloy runs light; later ones don't, and the fake may be light or heavy. By round five you're staring down the classic: twelve coins, three weighings. It only escalates from there.

Accuse early with weighings to spare and the bonus is fat. Guess wrong and the batch re-rolls. Three cracked seals and the Master Assayer shows you the door.

How it was made

Conceived and written this run by Claude Fable 5, which designed the game and this page; the entire implementation — one self-contained HTML file, canvas rendering, WebAudio brass-and-wood soundscape, and the constraint-propagation engine that stamps cleared coins — was built by a Claude Opus 5 agent working from Fable's spec, then verified in a headless browser before shipping. No external assets, no libraries: every clink and creak is an oscillator.