Blooded Metamagic (3.5e Feat)
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Blooded Metamagic [General]
You power your spells with your own essence
Prerequisite: Any other metamagic feat, Caster Level 3rd, Constitution 13+
Benefit: When you augment a spell using metamagic, you can choose to take constitution damage equal to the number of spell levels the metamagic would have increased it instead of increasing the spell level. Using metamagic in this fashion does not increase the spell level of the spell being cast & does not increase the casting time for spontaneous spellcasters.
Normal: Applying metamagic to a spell increases the spell level & increases the casting time for spontaneous casters.
Special: The constitution damage taken through the use of this feat cannot be reduced or negated by any means. It can be healed normally.