I really like the game! the simple game mechanics made the game a bit more addicting to me cuz I can build up more and more green circles behind me. My strategy was to build a trail of triangles at the corner, and hide behind it, I can then wait until the current wave dies, to move to the next wave. Since I mostly one shot all triangle enemies! I got until the required evolution is 2k per upgrade I think, then I stopped :P