Reserves of Strength (3.5e Feat)
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Reserves of Spell Strength [Magical]
When you cast a spell, you can choose to increase its effective caster level at the cost of damaging yourself.
Benefit: When you cast a spell, you can decide to increase your caster level with that spell by 1, 2, 3 or higher, but you take 1d6 damage per increased caster. Your increased caster level affects all level-based variables of the spell, including range, area of effect, spell penetration, and the difficulty of dispelling the spell. You can exceed the normal level-fixed limits of a spell with this feat, so a 9th-level wizard could use Reserves of spell Strength to cast a Fireball as a 12th-level wizard and deal 12d6 fire damage.