Caro rules and tips
Caro is the Vietnamese form of five in a row, usually drawn on squared paper in a school notebook. Players take turns marking one empty square, one with X and one with O.
The rules
- The board is 15x15, and X moves first.
- A line of five or more in a row, in any direction, wins.
- A line blocked by the opponent at both ends does not win. The edge of the board does not count as a block.
- If the board fills up with no winner, the game is a draw.
First steps to improve
- An open three, three in a row with both ends free, is a threat you must answer at once.
- The winning idea is a double threat: one move that makes two lines at the same time, because your opponent can block only one.
- Stay near the centre, where lines can grow in every direction.
- Defend early. It is far easier to block a three than to stop two fours.