This is a game that tests eyesight and logic. Players need to observe the color and direction of the shells fired by the cannon to adjust the color of the wall in the corresponding direction. The color of the shell that hits the wall matches the color of the wall to score. If the color of the shell that hits the wall is not the same as the color of the wall, the game fails. The wall is selected by dragging the left side joystick. the wall color is set by tapping on the right side color buttons.