The board, and how you win
- The grid is 3×3, 4×4 or 5×5. Tiles are numbered 1 upwards, and one square is empty.
- You win when the tiles read 1, 2, 3 … in order from the top left, with the gap in the bottom right corner.
- There is no game over. The puzzle cannot be made unsolvable, and there is no way to get stuck.
Tiles carry numbers, never pictures. A number needs no translation, stays readable at 5×5, and adds nothing to the download.
Controls
- Tap a tile next to the gap and it slides in.
- Several tiles at once: tap a tile further along the same row or column and everything between it and the gap shifts together. Three tiles moving counts as three moves — it is a shortcut for your fingers, not for your score.
- Swiping works the same way.
- Tapping a tile that shares neither a row nor a column with the gap does nothing.
Moves, time and Undo
- Your move count is shown while you play. It is the puzzle’s own measure, and it does not rush you.
- No clock is shown during play. Time is recorded and appears on the finish screen and in statistics.
- Undo is unlimited and free. It also rewinds the move count — you took the move back, so the count goes back with it. A multi-tile move is undone in one step.
- There is no Hint, and that is deliberate: nothing on this board is hidden. A hint here would have to be the next move of an optimal solution, which is very close to solving the puzzle for you. Undo and a fresh start are enough of a way out.
Why every board can be solved
Boards are not shuffled by scattering the tiles at random. They start solved and are then taken apart with legal moves only, never immediately undoing the move just made.
Because only legal moves are used, the board can always be walked back the way it came. There is no need to scatter the tiles and then test whether the arrangement happens to be solvable.
Levels and the Daily
- There are only three sizes, so the real difficulty knob is how deeply the board was shuffled. A deeper shuffle means a longer shortest solution.
- Levels unlock in order and can be replayed; the board for a level never changes. Your fewest moves and fastest time are kept for each one.
- The Daily puzzle is 4×4 every day, shuffled to the same depth. No weekday is harder than another, past days can be played, and no streak is counted.
| Levels | Size | Shuffle depth |
|---|---|---|
| 1–30 | 3×3 | 20 → 60 |
| 31–120 | 3×3 | 60 → 120 |
| 121–400 | 4×4 | 80 → 200 |
| 401–700 | 4×4 | 200 → 400 |
| 701–999 | 5×5 | 200 → 500 |
A method that always works
Solve the board in a spiral: finish the top row, then the left column, then treat what is left as a smaller puzzle and repeat. Never disturb a part you have finished.
- Place the tiles of the top row from left to right, but leave the last two for a moment.
- For the last two of a row, put the final tile directly below where it belongs, place the second-to-last in the corner, then rotate the pair into place. Trying to slot the corner tile in first is what makes the last two feel impossible.
- Do the same for the left column, top to bottom, leaving the bottom two of the column as a pair.
- When a 3×3 remains, rotate the outer ring until it falls into order — from here it is a small puzzle rather than a large one.
- Use Undo freely while you learn the pair rotations. It costs nothing and rewinds the move count with you.
Questions people ask
Can a board be impossible to solve?
No. Every board starts solved and is shuffled with legal moves only, so the path back always exists.
Does moving three tiles count as one move?
No, it counts as three. The multi-tile move saves taps, not moves.
Why is there no Hint?
Because nothing is hidden on this board. A hint would have to hand you the next optimal move, which is most of the puzzle. Undo is the way out instead.
Are there picture puzzles?
No. Tiles are numbers only, which keeps them readable at 5×5 and keeps the app small.
Is there a timer?
Your moves are shown while you play; the time is recorded quietly and shown after you finish.