Puzzle: Underwater World is a classical puzzle game invented in 1878, it’s still popular today. The sliding puzzle that consists of a frame of numbered square tiles in random order with one tile missing. The object of the puzzle is to place the tiles in order by making sliding moves that use the empty space. The game 15 puzzle is made in three different sizes: 3 х 3 (8 tiles) – for beginners and kids 4 х 4 (15 tiles) – classical size fifteen puzzle for all ages 5 х 5 (24 tiles) – for those who like to think Features: Three levels of complicity (8, 15, and 24 tiles); Algorithm that excludes unsolvable combinations; Realistic animation and tiles sliding Moves counter and timer Friendly interface with color theme Online records services Optimized for PC