The guardians of the galaxy!
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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Peanut butter and jellyfish.
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I'm going out tonight!
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A whole synod. One to move that the bulb be changed while the others debate until the room spins.
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One's a spineless, poisonous blob. The other is a form of sea life.
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Bike helmets don't fit hippos
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Unfortunately, no pun in ten did.
or