Players are a finicky bunch. They have a disturbing tendency to become incredibly destructive when they are bored or without direction. This happened in a game I was in over the weekend. I would declare it not my fault, but it was totally my fault. In my defense I only suggested burning down the house of a suspected vampire in broad daylight to try to flush him out. It was the other players that suggested we torch a neighboring town for practice before burning down the town with the vampire. This is why you don't let your players become bored or directionless.
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