By means of this spell, the magic-user bestows total invulnerability to hurled and projected missiles such as arrows, axes, bolts, javelins, small stones and spears. Furthermore, it causes a reduction of 1 from each die of damage inflicted by large and/or magical missiles such as ballista missiles, catapult stones, and magical arrows, bolts, javelins, etc. Note, however, that this spell does not convey any protection from such magical attacks as fireballs, lightning bolts, or magic missiles. The material component of this spell is a piece of tortoise or turtle shell.