I really enjoyed this game for a few days but once the levels start getting more challenging, the weaknesses show through. The game currency (which you oay real $ for of course) is diamonds. I dont begrudge a devleoper trying to make some cash but you dont just buy extra lives but also extra time in timed puzzles and (the real annoying part) keys to move on to the next level once you get to the next locked area (you can choose to wait several hours instead of buying keys.) The problem is that there are some puzzles that are just not well designed and you have to rely on a hefty amount of luck in order to succeed. With that in mind, Id never spend money on this game knowing that the money might be spent in hopes that Ill happen to get a good setup on the next stage. The look and the music are great (the music will get stuck in your head) and the puzzles can be very fun. But the developers also has some very frustrating design choices.