Sneak Spell (3.5e Feat)
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Sneak Spell [Sneak Attack]
You are able to take advantage of gaps in your opponent's defence to deal more damage with spells.
Prerequisite: Sneak Attack +1d6 or more, spellcasting ability (arcane or divine).
Benefit: When casting any spell that requires an attack roll and deals damage, if you would be able to make a sneak attack with a normal attack, you may add your sneak attack damage to spell damage. Ranged attack spells can only take advantage of this if the target is within 30 feet, as usual for a Sneak Attack. This feat cannot be used against creatures that are immune to critical hits.
Normal: Sneak attack damage cannot be added to spell damage unless the weapon-like spell variant in CAr is being used.