So, I've finished building my "Island of Logic!", where there are a number of puzzles for travellers. So far, I have a bunch of rivers with river craft, wolves, goats, and cabbages; and a number of areas with people who always lie and others who always tell the truth. There's also a sudoku room, and a few other similar places.
Of course, there is the classic "two doors, two guards" room, but since this is a tourist destination, and I actually want return visitors, the "bad door" leads to a room with nothing but sofas (but no coffee) and another exit, and the "good door" leads to the souvenir shop and cafe (which has sofas and coffee) and another exit.
During my final inspection before opening to the public, I found a problem: One of the guards from the "two guards, two doors" room had been working a double shift in one of the other knight/knave areas, and has had to take some time off. I'm not sure which guard it was, and I don't really want to ask the other one... No matter! The opening weekend must go ahead.
So, what I need from you, is this: what question do I ask the one remaining guard to get to the souvenir shop, and when the guard points to a door, do I take it, or take the other?
(Attribution: The two doors/two guards is extremely well known, and I don't know the origin. As far as I am aware, this variant is mine, but I wouldn't be surprised if someone else has also created it before).
TLDR:
There are two doors, one of which you want to use, the other you don't. There is one guard, who might be a knight (always tells the truth), or a knave (always lies). You may ask one question, and then must take a door. What's the question?
