As an action, you touch a willing creature who isn’t wearing armor, and a protective field of force force surrounds it until the spell ends. The target’s Defense becomes 13 + half its Aptitude Bonus (min 1) + its Dexterity (max 4). The spell ends if the target dons armor or if you dismiss the spell on your turn (no action required). The force can be invisible or can appear as a colored glow, at your option.