Notes on this puzzle
This medium slider scatters 15 tiles across a 4×4 tray, with the gap in row 4, column 2. 6 tiles start in their home squares.
Add up how far each tile is from its home square and you get 14. 2 pairs of tiles already sit in their correct line but in the wrong order, which pushes the minimum to at least 18 moves. The shortest possible solution is exactly 28 moves. Matching it is a real achievement. Solving it row by row, the method from our guide, takes 44 moves on this board. Tile 4 has the longest trip home: 2 squares.
Where to beginTiles are not far from home after this short shuffle; fix one corner, then grow outwards from it.