Rocks fall, everyone dies
"Rocks fall, everyone dies" is a method of ending a campaign commonly used by angry DMs who have gotten fed up with their players' bullshit. In this situation, the characters are arbitrarily killed by some unavoidable fate such as an avalanche or a cave-in (the titular rocks falling) and the DM declares this the end of the game.
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The original appearance of the "Rocks fall" phrase, according to Twenty Sided Blog.