"Wait, that didn't work right" - the Dysfunctional Rules Collection

[deuxhero]

Oh, boy, I can't believe I missed this. In Pathfinder, you have to make a DC 15 Knowledge (the planes) check in order to know what plane you're standing on. And you have to be trained to even attempt that check.

GM: The earth elementals are charging the army of air elementals at this moment. You have two rounds to act.
Fighter: Well, we're on the Elemental Plane of Air, so they'll be weakened. Cleric-
GM: Whoa, whoa, whoa. You don't know that you're on that plane.
Fighter: Uh... that's sort of where we've been this whole campaign.
GM: Make a Knowledge (the planes) check.
Fighter: I have no ranks.
Wizard: Let me. *roll* 11.
GM: Nope. None of you have any idea where you are.

And, of course, you don't even know when you're on the Material Plane. That's right.

If you don't have 16 INT (+3, on top of 1 rank for trained), you're a terrible wizard and deserve to fail that check.