Reversi
How to play Reversi
Outflank your opponent's discs on an 8x8 board to turn them your colour.
About Reversi
Reversi is played on an 8x8 board, starting from four discs in the centre, and Black moves first.
The player with more discs at the end wins, and empty squares left at the end are counted for the winner.
The goal of Reversi
Reversi is played by two players, Black and White, with discs that are black on one side and white on the other. Each move traps a line of your opponent's discs between two of yours and turns them over to your colour. When the game ends, the player with the most discs of their colour wins, or in Anti Reversi the player with the fewest. Here you play against a computer player, or against another person at an online table.
How to set up Reversi
Reversi and Anti Reversi are played on an 8x8 board, and Reversi 6x6 on a 6x6 board. The game starts with four discs on the four centre squares, two of each colour set diagonally, with Black on d5 and e4 on the 8x8 board.
Black moves first. The colours are drawn by lot at the start of each game, so you may play either. There is no limit to the number of discs each player may place.
Reversi rules
On your turn you place one disc of your colour on an empty square so that it traps at least one straight line of your opponent's discs between the new disc and another of yours, across, down or diagonally, with no gap in the line.
Every trapped disc in every direction is turned over to your colour, and only those. A disc turned over by a move does not turn any further discs, and a placed disc never moves.
If you have no move that traps a disc, you pass and your opponent moves again. You may not pass while you have a legal move, and a pass is made for you.
The game ends when neither player can move, either because the board is full or because no move is left for either side.
How to win at Reversi
In Reversi and Reversi 6x6 the player with more discs of their colour at the end wins, and equal discs are a draw.
If squares are still empty when the game ends, the official score gives them to the winner, and a draw is scored half and half: 32 to 32 on the 8x8 board and 18 to 18 on the 6x6 board.
In Anti Reversi the player with fewer discs at the end wins, and equal discs are a draw. The score is the discs as they stand, with no empty squares added, so losing every disc wins the game.
Reversi strategy tips
Take the corners when you can. A disc in a corner can never be turned over, and it gives you safe discs along both edges.
Avoid the squares next to an empty corner, above all the diagonal one: a disc there often hands your opponent the corner.
Early in the game, having more moves to choose from matters more than having more discs. Keep your discs few and central, and leave your opponent short of moves.
Near the end, try to make the last move in each empty region of the board, so that your opponent is the one forced to open new areas.
In Anti Reversi a corner disc can never be turned over, so it stays yours to the end and counts against you.
Reversi questions and answers
Who moves first in Reversi?
Black moves first. Here the colours are drawn by lot at the start of each game, so you may play either.
What happens if you cannot move in Reversi?
You pass, and your opponent moves again. The pass is made for you, so you never have to press anything. If neither player can move, the game is over.
Can you pass in Reversi?
Only when you have no legal move. As long as you can place a disc that turns over at least one of your opponent's discs, you must play.
How is Reversi scored?
Each player counts the discs of their colour, and the higher count wins. If the game ends with squares still empty, the official score gives them to the winner, and a draw is split equally.
Can Reversi end in a draw?
Yes, when both players finish with the same number of discs. On a full 8x8 board that is 32 each.
What happens when the board is not full at the end?
The game can end early when neither player has a move, for example when one player has lost every disc. The empty squares are then added to the winner's score. In Anti Reversi they are not, and the discs are counted as they stand.
What is Anti Reversi?
It is Reversi with the aim turned round: the player with fewer discs at the end wins. The moves, the passes and the end of the game follow the same rules.
Why is 6x6 Reversi different?
It is played on 36 squares instead of 64, so a game has at most 32 moves and is over sooner. The rules, the start and the scoring are the same, and a draw is scored 18 to 18.
Can you play Reversi online with a friend?
Yes. Sign in, follow the Multiplayer link and open a table for two, choosing Reversi, Reversi 6x6 or Anti Reversi, then send your friend its code or list the table in the lobby. A player who takes more than 60 seconds over a move has the computer move for them, and a player who leaves loses the game while the computer plays their side to the end.
Can you play Reversi against the computer?
Yes, every Reversi page is you against a computer player, and you do not need to sign in. The menu beside New game sets it to Easy, Normal or Hard, and Undo takes back your move and the computer's reply as often as you like.