If you upgrade molotov, mines and "secondary weapons" to the max, you could build walls of fire and mineas around you and kill everything without shooting once. 3 stars guaranteed in most levels.
It seems like you find a good way to making this mechanic "difficult" from level 52 onwards. Too many levels without a real challenge. Good concept however. (sorry for my english)
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 "Shape Fold Animals"){kind=icon}
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