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You can use your bane ability to inflict nonlethal damage.
Prerequisite: Bane class feature.
Benefit: While a weapon you wield is under the effect of your bane class feature, you can spend a swift action to switch between dealing lethal or nonlethal damage with bane. While your bane effect allows you to deal nonlethal damage in this way, you take no penalty on your attack roll for using a lethal weapon to deal nonlethal damage.
Normal: When using a lethal weapon to deal nonlethal damage, you take a –4 penalty on attack rolls.