Fun game, but as others have said before me: the energy is a real issue. 90 seconds for 1 energy, when you need 20 energy on average to remove 1 obstacle? There's even obstacles that need 100+ energy, and I'm only the first Island. And if you're wondering; the tl;dr of the FAQ on how to get more is "Do other activities that will also require you to wait a long time, or pay up".