This time, something I want to see in a game, in some form:
Me: "You see a cat."
Player 1: "What is a cat doing in a dungeon?"
Me: "Not much, mostly just standing around. It has started walking toward you though."
Player 1: "I back away from it, preparing to draw my sword if it attacks"
Me: "The cat explodes."
Inspired by a monster I came up with.