SRD:Triple-Throw (Epic Weapon Enhancement)
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This special ability can only be placed on a weapon that can be thrown. (If this property is rolled for a weapon that cannot be thrown, reroll.) A triple-throw weapon creates two duplicates of itself when thrown. Both the original and the duplicate weapons attack separately (at the same attack bonus). Regardless of the success of any of the attacks, the duplicates immediately disappear after the attack is completed. Any bonuses on damage due to accuracy or precision (including those from sneak attacks, the Precise Shot feat, or the ranger’s favored enemy bonus) apply only to the original weapon’s damage, not to the duplicates.