Ant Might (Fallout Supplement)
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All your fights with Fire Ants have made you tougher and given you the ability to better resist fire.
Prerequisite: Kill 30 Giant Fire Ants.
Benefit: +1 Constitution, Damage from fire is halved, +3 on Reflex Saves to put fire out.
Special: The effects of this feat stack with the Ant Sight feat.