A full-round action that allows an attacker to attempt a killing blow against a helpless opponent. A coup de grace can be administered with a melee weapon, or with a bow or crossbow if the attacker is adjacent to the opponent. An attacker delivering a coup de grace automatically scores a critical hit, after which the defender must make a Fortitude save (DC 10 + damage dealt) or die. Rogues also gain their extra sneak attack damage for this attack. Delivering a coup de grace provokes attacks of opportunity from threatening foes. A coup de grace is not possible against a creature immune to critical hits.