Nine boards inside one board. A clean blank grid with heavy dividers so the small boards stay readable in pencil — and the send rule printed underneath for anyone learning it.
Ultimate Tic-Tac-Toe takes the game everyone already knows and makes it deep enough to be worth playing. The board is nine small tic-tac-toe boards arranged in a three-by-three grid. To win the game you must win three small boards in a row.
The whole game hangs on one rule: the cell you play in decides which board your opponent plays in next. If you play in the bottom-left cell of any small board, your opponent must make their next move somewhere in the bottom-left board. If that board is already won or completely full, they may play anywhere.
This turns every move into two decisions at once — the move you want to make here, and the board you are willing to hand over. A winning move that sends your opponent to a board where they win outright is usually a bad move.
The board is sized to fill a single portrait page with room to write. Print two copies if you want a best-of-three, or print at 50% two-up if you prefer a smaller grid.