I am reminded of another puzzle: There are three doors numbered 1, 2 & 3. Behind ONE door is something you prize; behind each of the other 2 doors is a donkey. Assume you don't want to win a donkey for this one. You pick one door. The MC then unveils one of the OTHER doors to reveal a donkey, and asks you if you're sure. The question is, Are you better of sticking with your original guess or switching to the other unknown door?

This is NOT the one about the gates to hell and the twin guardians.