Umbral Spell (4e Feat)
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Umbral Spell [Metamagic]
Your spells are as dark as the darkest night.
Prerequisite: Wis 13, wizard
Benefit: Choose one area or close wizard attack spell that you know. When you use the power, you can add the following effect: squares of a zone with the radiant keyword that fall under the area of effect of your power are dispelled, and light sources in the area are extinguished.