Passwall was a transmutation spell that breached walls. The maximum thickness of the wall depended on the magical power of the caster.
The caster could create a passage through wooden, plaster, or stone walls, but not through metal or other harder materials. If the wall's thickness was too great, then a single casting of passwall simply made a niche or short tunnel. Several passwall spells could be cast in succession to form a continuing passage to breach very thick walls. When a passwall spell ended, creatures within the passage were ejected out the nearest exit. If someone dispelled the passwall effect, or if the caster dismissed it, creatures in the passage were ejected out the far exit if there was one, or out the sole exit otherwise.
Most of the creatures native to the elemental planes of Earth, Dust, Magma, Minerals, and Ooze had an innate ability similar to passwall. It was limited to stone materials, but they could extend it to any creature they were touching.
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