Blood Component (3.5e Feat)
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Blood Component [Epic Feat]
Sacrifice HP instead of XP for spells/powers.
Prerequisite: Character level 21+, Constitution 25.
Benefit: Instead of paying XP for certain spells or powers, you may sacrifice HP. 1 HP lost counts as 100 XP. The HP loss counts as vile damage, as found in the Book of Vile Darkness Vile damage can only be healed by magical means, and even then only within the area of a consecrate or hallow spell. For instance, casting wish with this feat would cost 50 hp instead of 5000 XP, limiting it's combat effectiveness.
Normal: If a character attempts to cast a spell with an XP component, he or she must burn the required XP. If this would cause the character to lose a level, the spell cannot be cast.