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Mind-boggling onslaught
rogue attack 15

Requirement: wielding a crossbow, light blade, or sling

Target: one creature

Attack: Dexterity vs. AC

Hit: "2[W] + Dexterity modifier damage."

Effect: Whether or not this rattling attack deals damage, the target takes the −2 penalty to attack rolls until the end of your next turn.

Sustain minor: The penalty to attack rolls lasts until the end of your next turn, or you can end the penalty and daze the target until the end of your next turn.[MP:81]

Mind-boggling onslaught is a daily power available to rogues at 15th level.