Phantom Prison

You completely surround a Large or smaller creature in immobile illusory walls, trapping it inside a false prison it can't escape. No other creatures see or feel these walls, and the target can't see anything outside of the illusory walls. The target can attempt a Will save when the spell is cast, each time it attempts to interact with or escape the walls, and each time something from outside the walls affects the target. On a success, it disbelieves the illusion, and the spell ends.