Drag a number from the bottom of the screen to a number on the grid — the two are added or subtracted. When three or more identical numbers sit adjacent horizontally or vertically, they merge into a single higher number in the farthest bottom-right tile of the group. Each match earns a star and a new card. Stars can be spent to remove a number from the board. Run out of cards and stars and the game ends. A number merge puzzle game.