The game is challenging even on the first few levels, especially since the designer astutely place rocks and other obstacles in your way. The higher levels makes it even tougher by adding stone ornaments (which you can push on to empty sand), and colored leaves you must 'collect' by stepping on them in the right order (yellow, then orange, then red). With a nice, mellow soundtrack, no time limit, and excellent graphics (I love the background animations that include leaves falling off sakura trees), Zen Puzzle Garden is both fun and soothing, as a Zen game ought to be. After getting the hang of gameplay mechanics, you will enjoy replaying the levels you already beat, just to make the sand patterns you create more artistic than the last time. Whether or not you enjoy unique puzzle games or just a relaxing brainteaser, Zen Puzzle Garden is well worth the price tag for the registered version, which contains over 60 levels. Two thumbs up, way up!