Double Edged Resistance (3.5e Feat)
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Double Edged Resistance [General]
You have conditioned your body to resist the elements, at a cost of becoming vulnerable to others.
Benefit: You must choose three of the five energy types: acid, cold, electricity, fire, or sonic. You gain energy resistance 10 against one of the energy type you have chosen, and take 10 additional points of damage from the other two.