Defensive Harmony grants affected creatures a defensive bonus by bestowing an enchanted coordination on their attacks and defenses. This allows a group of creatures to act as a single unit for a single battle or encounter. The effect is always centered on the caster, but affects all allies within a 15-ft. radius. Those affected can move outside of this area after the spell is cast and still enjoy the benefits of the harmony. While the spell is in effect, each affected creature gains a +2 bonus to [their] Armor Class. This lasts for 6 rounds or until dispelled.