Wall of Stone

Conjuration (Creation)
Level: Acolyte 5, Mage 5; Components: V, S, M/DF; Casting Time: Attack action; Range: Medium (100 ft. + 10 ft./level); Effect: Stone wall whose area is up to one 5-ft. square/level (S); Duration: Instantaneous; Saving Throw: See text; Spell Resistance: No
This spell creates a wall of rock that merges into adjoining rock surfaces. The wall of stone is 1 inch thick per four caster levels and composed of up to one 5-foot square per level. You can double the wall's area by halving its thickness. The wall cannot be conjured so that it occupies the same space as a creature or another object.
A wall of stone can be created in almost any shape the caster desires. The wall created need not be vertical, nor rest upon any firm foundation; however, it must merge with and be solidly supported by existing stone. If used to bridge a chasm, if the span is more than 20 feet, the wall must be arched and buttressed. This requirement reduces the spell's area by half.
Like any other stone wall, this one can be destroyed by explosives or brought down by bludgeoning or piercing weapons. Each 5-foot square has 15 hit points per inch of thickness and hardness 8. A section of wall whose hit points drop to 0 is breached. If a creature tries to break through the wall with a single attack, the DC for the Strength check is 20 + 2 per inch of thickness.
It is possible to trap mobile opponents within or under a wall of stone, provided the wall is shaped so it can hold the creatures. Creatures avoid entrapment with successful Reflex saves.