Flood lights!
or
If one side has one, the other side has to get one. Once launched, they cannot be recalled. When they land, they screw up everything forever.
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They screw millions of bulbs every day, but when it comes to your bulbs, there's no record.
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Nearly unanswerable, since the one who tries to change it usually drops it, and the others call for a planning session.
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Climb up a tree and act like a nut
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It takes two to tangle!
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A newspaper!
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Pointless
or