Scar Magic (3.5e Feat)
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Spell Scar [Arcane]
A terrible affliction turned into a powerful weapon.
Prerequisite: Able to cast 3rd level spells
Benefit: You may cast spells from your affected body part, negating certain spell requirements. You are immune to damage from your own spells, even when reflected.
Special: You take double damage from any magical source, but cannot be killed by magical sources, only knocked unconscious. You also take a -4 penalty to saves against spells.