Gloom Strike (4e Feat)
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Gloom Strike [General]
Your sneak attacks leave a residue of darkness that clouds your enemy's vision.
Prerequisite: Extra damage class feature +3 dice, Drow, Darkness racial power
Benefit: When you use your extra damage class feature to deal extra damage to an opponent you can use this feat. If you do so,the number of dice rolled for the extra damage dealt by your extra damage class feature class feature is reduced by 2. In addition, the opponent you used your extra damage class feature class feature on takes a -2 penalty to perception checks, and all creatures have concealment against that opponent until the end of your next turn.