The game is played on a grid with numbers from 1 to 9 in each of the squares.

The objective is to place the numbers such that they add up to the number that is located in the center of the grid, which is 9 in this case.

To complete a puzzle, you need to use logic and intuition. You can see the solution to a puzzle as soon as you think of it. However, you should not be afraid to make mistakes. You can correct them later.

The difficulty of a puzzle increases with time. The game is designed to be played by anyone, regardless of age or ability.