The goal is to restore the original state of the board, after being mixed up by the Scramble button.

One of the tiles is missing from the grid, so an adjacent tile can be slided towards the empty place.

The tiles can be set to be textual (letters or numbers), or they can be pieces of a picture. For the former case, the solved state is ascending/alphabetical order (in reading order), and in the latter case, the picture must be reassembled from the pieces. In a solved state, the missing piece is always in the bottom right corner.

Mouse control: click on a tile to slide it towards the empty place. You can also slide multiple tiles at once in the same row or column.

Keyboard control: use the arrow keys to slide tiles towards the empty place.

Touch control: grab a tile and move it towards the empty place.