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warlock (fey) attack 1

Target: one creature

Attack: Charisma vs. Reflex

Hit: "2d6 + Charisma modifier fire damage, and the target takes a −2 penalty to attack rolls until the end of your next turn."
Fey Pact: "The penalty to attack rolls is equal to 2 + your Intelligence modifier."[PH:132][U :W]

Witchfire is an encounter power available to warlocks at 1st level.