Ethereal barrier

Ethereal barrier was an abjuration spell that prevented encroachment by creatures moving through the Ethereal Plane.

Effects
The wall(s) created by this spell were proof against creatures traveling through the Ethereal Plane by phasing, dimension door, shadow walk, or any other method of travel through the Border Ethereal adjacent to the plane of the caster (usually the Prime Material Plane). To those on the same plane as the caster, ethereal barrier was undetectable. This spell did not prevent travel through the Astral Plane (teleport, gate, etc.).

The area of effect was two 10 ft (3.1 m) squares per level of the caster, arranged any way the priest desired. Multiple priests could cooperatively cast this spell for a greater duration, combining their areas of coverage. It took ten minutes to erect an ethereal barrier.

Components
Besides verbal and somatic components, a compound of lead and rare earths was required. Estimated cost was 10 gp per square.