Object : recreate the starting configuration.
 
First Click the board to randomize it. Then click any circular token that has six neighbours. The neighbours will rotate clockwise.
You win when you can recreate the original setup.
 
Variants S-1, S-2, ...: various setups on small board.
Variants M-1, M-2, ...: various setups on medium board.
Variants L-1, L-2, ...: various setups on large board.
 
Hint: for the more complicated variants you might want to open the game twice so that you have a permanent image which reminds you what the target board setup is.