1. The board
Nine tic tac toe boards form a larger 3 by 3 grid. The starting player uses blue Xs and the other player uses red Os. On the first turn, choose any of the 81 squares.
Ultimate Tic Tac Toe Rules
Detailed rules and gameplay guidance for Ultimate Tic Tac Toe.
2. Sending your opponent
The position of your square determines the board your opponent must play in next. For example, choosing the top-right square in any small board sends your opponent to the top-right board. The centre square sends them to the centre board.
3. Winning a small board
Make three of your marks in a row, column, or diagonal to claim a small board. It is then closed, even if it has empty squares. A full board with no winner is drawn and closed; neither player claims it.
4. Free choice
If your move sends your opponent to a board that has already been won or drawn, they may choose any empty square in any open board. This also applies if your move closes the board it sends them to.
5. Winning the game
Claim three small boards in a row, column, or diagonal on the large grid to win. Drawn boards never count toward a winning line. If all nine boards close without a winning line, the game is a draw.