You attack the weak spots in your opponent's armor, not only dealing damage but also leaving your prey vulnerable to later attacks.

Encounter   ✦     Martial, Weapon
Standard Action      Melee weapon

Requirement: You must be wielding two melee weapons.

Target: One creature

Attack: Strength vs. AC (main weapon and off-hand weapon), two attacks

Hit: 1[W] + Strength modifier damage per attack. If one attack hits, the target takes a penalty to AC equal to your Wisdom modifier until the end of your next turn. If both attacks hit, the target takes a penalty to AC equal to 2 + your Wisdom modifier until the end of your next turn.

Published in Player's Handbook, page(s) 109.