Coup de Grace

You may take advantage of a creature's Helpless condition with Coup de Grace. To perform a Coup de Grace, target an adjacent helpless creature with a Melee Basic Attack or Ranged Basic Attack. This attack provokes an opportunity from threatening opponents. If you hit, in addition to dealing damage, the target must make a Resilience check [DC 15] or it suffers an automatic Lethal Injury. If the target has already been reduced to 0 hitpoints, it suffers a -10 penalty to its Resilience Check (instead of making an additional Injury Check). If the target succeeds the Resilience Check, it must make an Injury Resilience Check, suffering an injury according to the result of the check.