Whack-a-Wirrn

From the worlds of TV's "Dr. Who"

Once again, the fiendish Wirrn have infested Nerva Beacon, and this time there's no Doctor or Sarah-Jane around. There's just you. They're hatching like, well, like Wirrn. Can you destroy enough before they take over the entire solar stack?
You have just sixty seconds to decide the future of the human race. Good luck!

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