One Empty Square, Fifteen Tiles to Put in Order

The missing square is the most useful piece on this board. Card Game Nook's Sliding Puzzle starts with numbered tiles in a scrambled frame and asks you to arrange them from left to right, row by row, with the empty space in the bottom-right corner. The familiar 4×4 frame contains fifteen tiles, while the options also offer smaller 3×3 and larger 5×5 boards. If you enjoy planning moves in 2048, this is a related grid challenge with a different goal: you sort the numbers rather than merge them. Click or tap a tile beside the empty square to slide it into the gap. You can also choose a tile farther along the same row or column to push the intervening line. The Moves counter counts each tile that travels one square, so moving a line of three costs three moves, not one. Arrow keys slide a tile in the direction of the arrow; they do not sweep every tile across the board as they do in 2048. Watch the gap as well as the tile you want to move, and use the Home counter to see how many numbers are already in their correct positions. A useful plan is to complete a top row, then a left column, while leaving those finished sections undisturbed. Before moving a number, think about how the empty square will reach the other side of it. Chasing one tile without planning the gap's route can undo the progress you just made. The Undo control lets you reverse a slide and compare a different approach. There is no need to treat a wrong turn as a lost game: reversing and reorganizing are part of learning how the frame works. Start with 3×3 if you want a smaller space to explore, or stay with the fifteen-tile board for a longer planning challenge. The three-dot options menu contains the board sizes, and New puzzle deals a different arrangement and resets the move counter. Changing the puzzle is a fresh start, not a completed solution. Follow your moves, the elapsed time and the tiles already home as you work toward the ordered board. The game is supplied by Card Game Nook, with its credit link kept visible beside the frame.