An AI shoots a rocket and it does an orbit around the whole level and ends up on the other side of his planet. And he used at leasy 2 rounds to figure that out.
Barriers do actually make a difference. When you advance you easily earn the money spent in a matter of seconds and it will still be standing there. I used a sort of patter with 8 spread in the middle, 4 barriers North - West - South - East and 4 different turrets in between. Then, to protect the turrets, 4 barriers out farthest, NW - NE - SW - SE... When you have upgraded everything all you need to do is to spend your money on creating ridiculously big amounts of barriers and guns. Win!
I had to check the walkthrough in the end but I managed fine so far. Here is a hint though, there is a third of those pouring things under the bird cage...
you can't be serious, I came to the boss level, but when I did it, I was logged out, and now it seems I have to start all over again to get the Heart of the Problem badge. GAH!!!
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