See Through (5e Spell)
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|V, S, M (a piece of glass)
You touch a simple surface such as a door, a wall, or even a shield to see through it as if it was transparent. The target area can vary from 1 to 5 square feet, as chosen when the spell is cast. The surface appears to be nonexistent from the side of the caster, yet the other side remains completely normal and solid.
The spell can see through most barriers, but it is blocked by 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt.