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rogue attack 7

Requirement: wielding a light blade

Target: one creature

Attack: Dexterity vs. Fortitude

Hit: "2[W] + Dexterity modifier damage. If the target moves 2 squares or more during its next turn, it takes damage equal to your Dexterity modifier.
Brutal Scoundrel or Ruthless Ruffian: The damage the target takes for moving equals your Strength modifier + your Dexterity modifier."[MP2:62]

Leg-breaker is an encounter power available to rogues at 7th level.