This game is really fun and engaging but it's simply too expensive to play past level 20. The plants, trees, rocks etc become very dense and more and more expensive as you level up. I just burned through $4 worth of energy and emeralds in 22 seconds. Yes, that's seconds not minutes. I tried a similar experiment with game hunting. It took me 165 energy to take out 1 bear. If you have tons of disposable income to spend you'll love it. If not it's probably not for you.