I have one. I was making a D-Day map from Highgrounds, and I wanted to simulate bombs falling from the sky on the beach side at regular intervals. To do this, I piled up about 4 or 5 crates and set a fusion coil on top. I set the respawn rate to 10 and deleted the crates below it. Fly up to the coil and run in to it so it triggers the physics engine to make it fall. That area will now be bombed every 10 seconds
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