⬛ Reversi

How to play

Reversi is played on an eight by eight board that starts with two white and two black discs in the middle. A legal move places your disc so that a solid line of opponent discs is trapped between it and another of yours, in any of the eight directions; every trapped disc flips to your colour. When neither side can move, the discs are counted and the larger total wins.

• 2 Players button — both colours are played by people on the same screen. Selecting it restarts the game.
• vs AI button — you take White and the computer plays Black, replying after a short pause. This also restarts the game.
• Board squares — click or tap to play. Squares that are legal for the side to move are marked, and clicking anywhere else does nothing.
• New Game button — resets the board to the four starting discs in the current mode.

Scoring

Your score is the number of discs of your colour on the board, shown live in the two panels and recounted after every move. Only the final count matters, and it is taken when neither player has a legal move, usually with the board full. If one side has no legal move but the other does, the turn passes back and the message line says so. An equal count is reported as a draw.

Tips

• Corners are permanent. A corner disc can never be flanked, which makes all four worth more than any other square.
• Avoid the three squares around an empty corner. Playing there usually hands the corner to your opponent.
• Holding fewer discs in the middlegame is often better. What matters is still having moves when your opponent runs out.
• The computer always takes the move that flips the most discs, so it can be baited with a large but poisoned capture.

Frequently asked questions