Ataxx screenshot.

Ataxx is a board game which first appeared in 1990 as an arcade video game by The Leland Corporation.

The game play is similar to that of reversi.

Two players take turns placing pieces on a 7x7 board. In the starting position, each player has two pieces of his color around diagonally opposite corners of the board. Player take turns placing pieces on the board by moving one of their pieces to an adjacent square. If moving to a neighboring (in any direction, including diagonal) square, the original piece remains on the board. If moving to a square one neighbor away, the original piece is removed. After the move, all neighboring enemy pieces around the new piece become your pieces.

The game ends when one or both of the players can't move. The player with more pieces wins.

The board may be of several different configurations, by having certain squares filled (not playable).

According to online resources, the game was invented by Dave Crummack and Craig Galley in 1988 and was called Infection. It was first programmed on Amiga, Commodore 64 and Atari ST. The game is purportedly in the public domain now.

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