Ataxx is a strategy board game similar to Othello / Reversi. Play against the computer with varying degrees of difficulty in this Ataxx clone version. See below for information on the game and how to play.

If you have trouble fitting it vertically onto your screen, resize the browser window to have the game resize also.

How to Play

Move your counters (blue spheres) to any adjacent vacant space (grey holes) to clone your existing counter. Moves can be made in any direction. Move two spaces in any direction to relocate your selected counter (without cloning).

Moving to a space adjacent to your opponent (red spheres) will convert all immediately adjacent counters to blue, effectively capturing your opponent.

The aim is to have the highest number of counters present once the board is full. An exception is where one colour totally converts the other and the board won’t be completely filled.

If a player can’t make a move, a subsequent move by the previous player can be made.

To make a move, click on a blue counter. If it goes dull, then that counter is immovable and another should be selected. Once selected, all possible destinations will be highlighted in light blue. Click on any of these to have the selected counter move from its original to new location.

Try to move to a location that will provide maximum conversions of red to blue. For example, if possible move into a vacant space surrounded by red counters to convert them. Bear in mind that the higher the selected difficulty level, the harder the computer (CPU) will be trying to convert your blue to red.


Start Game

Click on the Start Game title to begin the game.


Use the up and down arrows to change and select the difficulty level. The level is indicated in the lower panel of the interface by bars in the lower right-hand corner. Alternatively, the bars themselves may be clicked to have the same effect as clicking on the up arrow. One green bar represents the easiest level while ten bars, increasingly red in colour is the hardest level. In the easier levels, the computer will play in an inebriated manner, often making dumb moves and hiccupping in the process.

There is also a special training mode where the computer will play equally well as you, if not a tiny bit better. This can be accessed by clicking the down arrow in the Difficulty row until no bars can be seen (or level zero). The computer also calculates your average playing ability across games in this mode and plays a little better accordingly. So the more good moves you do, the computer will also play increasingly better moves.

Board Size

The board size (or grid) can be increased or decreased by clicking on the respective and corresponding up and down arrows. Tee smallest grid is 4×4, while the largest is 16×16. Obviously, the larger the board size, the longer the game will be to complete. Also, the more processor intensive it will be due to the increase in necessary calculations for moves and depending on your computer and browser, the animations may become slower.

The standard board size is a 7×7 grid and with this size there are several board types available. See the next section for further information on these.
Note that when a board size is anything other than 7×7, the Board Type option becomes greyed out.

Board Type

There are nine different board types available within the 7×7 grid. These can be scrolled through by clicking on the left / right arrows beside the Board Type option or by clicking on the small board type thumbnail in the lower panel on the left hand side. The difference in each is a varying pattern of void squares that cannot be occupied by any counter, thus limiting certain moves. One is not necessarily more difficult than another, just different.

CPU vs. …

This option allows you to fully automate a game if desired, to have the computer play moves for you. To distinguish this from the normal mode, blue counters are replaced with green counters. To activate this, click on the blue ‘YOU’ option to change it to read ‘CPU’ (in green). Clicking this again will change back to ‘YOU’ restoring the normal playing mode. The automated CPU mode can be interesting to watch and learn how to play through observation. All other options can also be applied within this mode and scores are recorded separately for each mode as indicated by the green and blue numbers in the lower panel.

Clear Scores

Scores are recorded during each move and applied to each tally. At the start of a new game, these scores (on the upper score line) are reset back to 002 because there are initially two of each counter on the board. After each game however, the winning game score (lower score line) is accumulated by one and this is retained and resumed when the game is reloaded in subsequent sessions. The game score can be reset by clicking on the ‘Clear Scores’ text at the base of the upper panel of the interface.


Once a game has started, options can’t be changed. Click on ‘Quit’ at any time within the game to return to the game options for making further changes.


This game is a work in progress, and may contain bugs and problems that will need to be addressed. The colours and interface are also temporary and may change with development as improvements are made. On the whole though, it is reasonably playable and enjoyable.