Excavate

Underdark (Und)Updated Forgotten Realms (3.5)

Excavate is a D&D 3.5 spell (Transmutation) from Und. On class lists for Sorcerer (Level 8), Wizard (Level 8), Abjurer Variant (Level 8), and others. Range or area: Close (25 ft. + 5 ft./2 levels); Saving throw: None; Duration: Instantaneous; Casting time: 1 standard action.

School
Transmutation
Casting Time
1 standard action
Components
V, S, M
Range
Close (25 ft. + 5 ft./2 levels)
Effect
One 5 ft. By 8 ft. opening, 1 ft./level deep
Duration
Instantaneous
Saving Throw
None
Spell Resistance
No

As with passwall, you create a passage through wooden, plaster, or stone walls, but not through metal or other harder materials.
If the wall’s thickness is more than 1 foot per caster level, then a single excavate spell simply makes a niche or short tunnel with the stated dimensions.
Several excavate spells can be used in succession to breach very thick walls by forming a continuing passage.
Unlike passwall, excavate is an instantaneous effect that does not end and cannot be dispelled; any passage it creates is permanent.
Material Component: A pinch of excavated earth.