Notes on this puzzle
This expert slider scatters 24 tiles across a 5×5 tray, with the gap in row 5, column 4. 1 tile starts in its home square.
Add up how far each tile is from its home square and you get 65. 2 pairs of tiles already sit in their correct line but in the wrong order, which pushes the minimum to at least 69 moves. Solving it row by row, the method from our guide, takes 181 moves on this board. Tile 10 has the longest trip home: 7 squares.
Where to beginOn 5×5, peel off the top row and left column twice; only then does the board become a familiar 3×3.