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Staggering assault
rogue attack 5

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

Target: one creature

Attack: Dexterity vs. AC

Hit: "2[W] + Dexterity modifier damage, and the target is slowed (save ends). If the target is not bloodied when you make this attack, the attack deals 1[W] extra damage."

Effect: "Until the end of the encounter, when you hit the target, it is slowed (save ends)."[MP:76]

Staggering assault is a daily power available to rogues at 5th level.