Twenty-one stones

How it works

1. Two players take one, two or three stones per turn. The player taking the last stone loses.
2. Tap the buttons or reach them with Tab and activate with Enter/Space. New game resets the round.

Example & practical use

Two players take one, two or three stones per turn. The player taking the last stone loses.

Limits and help

Runs on this device. No online multiplayer, prizes or money. Puzzles and memory games are not medical or ability assessments.

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Troubleshooting

Try the small example on this page first. If it works, check your input format and size limit. Save any needed input before reloading. You do not need to share a file or password to report an issue.

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