Euthanize (3.5e Feat)
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With special cares, such as poison, needles or similar method. You may peacefully kill a helpless creature.
Prerequisite: Base Attack Bonus +4.
Benefit: You may, as a full-round action who provoke AoO attempt to Euthanize a helpless creature. Euthanize is similar to a coup de grace but grant no save.