Fortress Shield

The wearer of this +1 tower shield may, as a full-round action, transform the shield into a 1-inch thick cube of iron that springs into being around him, completely enclosing his space. The cube has hardness 10 and 30 hit points per side. This cube grants the wearer total cover against everything outside the cube, including (as it is perfectly sealed) swarms and gas attacks. The inside of the cube is dark, and air cannot get in or out so the wearer must hold his breath starting on the third round after activating the cube. Attacks sufficient to destroy one side of the cube cause it to immediately transform back into a shield, which loses half its hit points and gains the broken condition. Otherwise, the cube reverts to shield form upon command, if the wearer moves from his current space, or the wearer falls unconscious or dies.