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Twin Thunders (Combat)
When you fight giants, your powerful blows combine with skills learned from generations of your people to quickly even the odds.
Benefit: Once per round, when wielding a bludgeoning weapon in each hand against a creature with the giant subtype, if you hit the creature with your off-hand weapon after you hit with your primary weapon, roll the damage dice for your off-hand weapon twice and add the results together before adding any bonuses. Such extra weapon damage dice are not multiplied on a critical hit.