Wardstone Imprint

You touch a door, window, chest, or 10-ft-square section of wall/floor. The touched area is imprinted with an invisible rune. For the next 24 hours, the first time a creature other than yourself touches it or passes through the rune, you immediately learn the location and true appearance of that creature. In addition, you instantly know the creature’s type and whether it was carrying magic items.

If you cast this spell on the same spot every day for a year, the effect becomes permanent until dispelled.