SRD:Wall of Ectoplasm

You fashion a roiling wall of ectoplasm, imbuing it with solidity. The wall cannot move once it is formed. It is 1 inch thick per four manifester levels and occupies up to one 5-foot 10-foot square per level. Each 5-foot 10-foot square of the wall has 10 hit points per inch of thickness and hardness 5. A section of the wall whose hit points drop to 0 is breached. If a creature tries to break through the wall, the DC for the Strength check is 15 + 2 per inch of thickness.

The wall of ectoplasm is susceptible to dispel psionics, but it gains a +4 bonus on any check to determine whether the wall is negated. Spells, powers, and breath weapons cannot pass through the wall in either direction (though they could damage it). It blocks ethereal creatures as well as material creatures (though ethereal creatures can usually get around the wall by floating under or over it through material floors and ceilings). The wall is opaque, so neither vision nor gaze attacks operate through it. The wall does not block psychoportive travel, such as that provided by the psionic teleport power.

You can form the wall into a flat, vertical plane whose area is up to one 10-foot square per level or into a sphere or hemisphere with a radius of up to 1 foot per level.

The wall of ectoplasm must be continuous and unbroken when manifested. If its surface is interrupted by any object or creature, the power fails.