SRD:Armor of Arrow Attraction
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Armor of Arrow Attraction: Magical analysis indicates that this armor is a normal suit of +3 full plate. However, the armor is cursed. It works normally with regard to melee attacks but actually serves to attract ranged weapons. The wearer takes a –15 penalty to AC against any attack by a ranged weapon. The true nature of the armor does not reveal itself until the character is fired upon in earnest.