The best defence setup is to put a column of virus attackers , one with worm attackers , and one with trojan attackers. To have enough processing power you can always put the coprocessors in the first column and if you want to trick the AI check Wertilq's comment in the highest rated section . This worked for me ^^
At level 30 ,choose the sticky ragdoll and aim at the big star between the big saturn and the small earth , then hit the bomb with a normal ragdoll and you win :D
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