This seems to be a real nice addition to your gameplay. Lovingly chaotic.
I don't know if im routined enough to handle it yet, but since they are appearing late game, i will give it a try.

They do appear "only" to the most polluting buildings or is there some sort of random appearing with them?

And is there any timer in-between attacks? in the video 5 appeared in very shortly next to another.

Oh, and can you just add this mod if you're "prepared"? i mean, by time of the evo-factor is high enough, you ARE pretty strong, but still.