Click an empty square to randomize the position.
Then click an arrow to change the order in a row, file or diagonal.
A row or file will be reversed in its order, but the tokens in a diagonal will be shifted diagonally by one position! (This diagonal shifting allows a much more thorough mix than just reversing a diagonal).

You win if you can recreate the original position.

Variant 2: 6x6 board
Variant 3: 8x8 board

Please note that there are six alternative piece sets available.