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Perfect strike
rogue attack 27

Requirement: wielding a crossbow, a light blade, or a sling.

Target: one creature

Attack: Dexterity vs. AC, Fortitude, Reflex
Special: You make one attack roll, and you hit if the roll equals or exceeds any of the three defenses.

Hit: "4[W] + Dexterity modifier damage. Add an extra 1[W] damage if the attack hits two defenses. The target is also stunned until the end of your next turn if the attack hits all three defenses."[PH:126]

Perfect strike is an encounter power available to rogues at 27th level.