Reversi Online

The modern version is based on the game reversi that was invented in 1883 by Englishmen Lewis Waterman in 1888. It enjoyed a brief flare of popularity, then faded into obscurity until it was resurrected in England at the end of the 19th century as Othello. In 1893, the German games publisher Ravensburger started producing the game. The modern rule set used on the international tournament stage originated in Mito, Ibaraki, Japan in the 1970s: the Japanese game company Tsukuda Original registered the game under the trademark name Othello. Goro Hasegawa, who wrote How to win at Othello, popularized the game in Japan in 1975.

The rules of Reversi or Othello are fairly simple but lead to a great many combinations and strategic decisions.

Game takes place between two players, black and white, on an 8x8 board of 64 squares. There are 64 reversible pieces coloured black on one side and white on the other. The board is set up initially with two black pieces placed on squares e4 and d5 and two white pieces on d4 and e5.

Black always plays first with players then taking alternate turns. At each turn a player must place a piece with their colour face up on one of the empty squares of the board, adjacent to an opponent's piece such that one or more straight lines (horizontal, vertical or diagonal) are formed from the newly placed piece, through one or more of the opponent's pieces and up to other pieces of their own colour already on the board. All the intervening pieces of the opponent's colour are flipped to the colour of the newly laid piece.

Once a piece is played, it never moned off the square, but it may be flipped several times, claimed first by one player, then the other. Players may not pass unless there is no valid move available to them in which case they must pass. Play continues until neither player is able to move, usually when all 64 squares have been played.

The winner is the player with most pieces turned to their colour at the close of play. By convention any empty squares at the end are added to the winners score. If both players have the same number of pieces at the end then the game is tied.