What is Order and Chaos?
Order and Chaos is played on a 6×6 board. One player is Order and the other is Chaos, and on every turn either of them may place an X or an O in any empty square. Order moves first. Pieces never move once placed.
Order wins as soon as five like symbols stand in a line, across, down or diagonally, no matter who placed them. A line of six counts too, since it contains five. Chaos wins if the board fills up without such a line, so the game never ends in a draw.
The two sides play very different games. Order builds open lines of four like symbols that can be finished at either end, so that Chaos cannot block both. Chaos spoils lines by dropping the opposite symbol into them, and tries to break every line before it becomes dangerous. Here Order sits in the X seat and Chaos in the O seat; the symbol you place is chosen separately on each move.
Rule changes
| Rule | Standard Tic-Tac-Toe | Order and Chaos |
|---|---|---|
| Board | Standard Tic-Tac-Toe3×3. The table setup also offers 4×4 and 5×5. | Order and ChaosAlways 6×6. |
| Players | Standard Tic-Tac-ToeX and O, each trying to complete a line of their own marks. X moves first. | Order and ChaosOrder, in the X seat, and Chaos, in the O seat, with opposite goals. Order moves first. |
| Symbols | Standard Tic-Tac-ToeEach player always writes their own mark. | Order and ChaosBoth players choose X or O on every move. |
| How to win | Standard Tic-Tac-ToeComplete a line of three of your marks. | Order and ChaosOrder: five like symbols in a line, placed by either player; a line of six also counts. Chaos: a full board with no such line. |
| Draws | Standard Tic-Tac-ToeA full board without a line is a draw. | Order and ChaosThere are no draws: a full board without five in a row is a win for Chaos. |
History
Order and Chaos was invented by Stephen Sniderman and introduced in a puzzle magazine in 1981. The rules here are the original ones, in which a line of six also wins for Order. Under those rules the game has been claimed to be a forced win for Order with perfect play.
Sniderman later proposed that six in a row should not count. That gives Chaos new ways to defend against Order's lines of four, and with that change the game has been reported to be a forced win for Chaos, which can follow a pairing strategy. The later rule is not offered here.