Beat all the levels.
It is nice blend between sokoban and snake. I stopped having difficulties when I learned how the levels were supossed to "flow", which throw clues in finding the proper order. For example a lot of times I could barely make a loop to escape a room by one square, which always meant I was on the right track to solving the level. It was fun, sometimes it required a lot of trial and error. I imagine more complex maps would take many many trials considering how the test map have doors.