Okay, as you likely know, nests will periodically produce an egg, that releases a flyer swarm that goes after a barricade.
Fighting them is easy: all you have to do to kill the nest is destroy the egg, then deal enough damage to the nest while it’s vulnerable afterwards. Any tower that can attack ground works for this, but I prefer just watching the nest and activating the Orbital Laser and one shotting the egg and nest.
Failing that, you can just destroy the egg each time it shows up.
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