Trouble Brewing

From Introduction:

The setting of Trouble Brewing is a lonely building capable of teleporting, so the encounter can be located in any terrain you see fit. Curiosity alone should ensure the players don't just opt to go around the peculiar building. As the encounter begins, the PCs are in the middle of some journey or another. As heroes, they are constantly on the move, so Trouble Brewing can be inserted in any of their travels. Wherever they are, it should be a relatively
isolated area so that the presence of a neat building will seem unusual.