Puzzle rectangular tags (also called Gem Puzzle, Boss Puzzle, Game of Fifteen, Mystic Square) and its variations, including a variant with pictures. The puzzle is a set of identical square tiles with numbers printed on them, lying in a rectangular box. One square field in the box remains empty. The goal of the game is to arrange the tiles in ascending order by moving them in the box, preferably with as few moves as possible.

The object of the game is to place the tiles in ascending order from left to right and top to bottom swapping them with the empty cage starting with tile number 1 in the top left corner and ending with the empty cage in the bottom right corner of the bo