Of cause, in the 3x3 level , it is quite easy that you may just pay a little effort to pass each round.
When you came into 4x4 and 4x6 levels , you need much more skills and patience . Even more , after 20th round of 4x4 and 4x6 levels , we put some obstacles to make the puzzle more interesting.
By the way, every round that provided in this puzzle are all solvable !!
Thank you for select the game , Enjoy !!