Fiendish Blood Casting (3.5e Feat)
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Fiendish Blood Casting [General]
The darkness in your blood shows in your spells.
Prerequisite: evil outsider or some form of fiendish blood (such as Abyssal Hereitor feats), Improved Blood Component
Benefit: When you use your blood component ability, the DC on all evil spells casted by you increases by +1.