Number Duel Game Mode

Subtraction Game

The Subtraction Game is a two-player arithmetic strategy game. Each player selects an active number, and the absolute difference between the two numbers becomes the target for the turn. Players then race to claim matching cells and connect four in a row on the board.

How to Play

  1. Choose your active number from 1 through 12.
  2. Subtract the smaller active number from the larger one. That difference is the target.
  3. Claim an open board cell that shows the matching target value.
  4. Connect four claimed cells horizontally, vertically, or diagonally to win.

Because the target is the absolute difference, the order of subtraction does not matter. This keeps the mental math clean and focuses the challenge on board positioning and number selection.

Example Turn

Your opponent's active number is 9. You choose 3. The target becomes |9 − 3| = 6. Every open cell on the board with the value 6 lights up. You claim one that extends your horizontal line. On the next turn, your opponent can shift their number to change the target — or pick a target that blocks your progress.

Why Play a Subtraction Game

Who Is This Game For

The Subtraction Game is ideal for elementary students who are building subtraction confidence, parents who want screen time with educational value, and anyone who enjoys light strategy games. Teachers can use it as a warm-up activity or a reward for early finishers.

For a more detailed rules breakdown and strategy tips, visit the Subtraction Duel mode page.

Related Game Modes

Play the Subtraction Game

Read the full rules