Via Negativa

Type: General
Source: Champions of Ruin

You can channel greater amounts of negative energy into your inflict spells.
Prerequisite: Ability to rebuke undead.
Benefit: As a free action, you can spend one of your rebuke attempts to deal additional harm with an inflict spell. You must spend the rebuke attempt before making the attack roll. If the attack roll succeeds, the inflict spell deals an extra 1 point of damage per character level (maximum +20). If the attack roll fails, the rebuke attempt is spent and wasted.

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