←→↑↓ move · Enter or Space places a stonetap a ringed place to put a stone there
Stone Garden
Reversi, raked in gravel
Put a stone where it closes a line of the other colour, straight or
slanting, between it and one of yours: every stone in that line turns.
The rings show where a stone can go. When neither colour can move, the
garden is counted, and the most stones wins.