Eric Anondson said:Well, then the smart non-mage villain has hired a mage, or rather a network of mages for every corner of his stronghold, or rather a network of mages for every corner of his stronghold at all hours of the day.
But that brings up the "contrived problem" that DMs like me try to avoid.
Somehow I think it's got something to do with the focus you place on the game.