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Armor-Piercing Thrust
Fighter Attack 3

Encounter ✦ martial, weapon

Melee weapon

Special: If you're using a light blade or spear, you gain a bonus to the attack and damage rolls equal to your dexterity modifier.

Target: One creature

Attack: Strength vs. Reflex

Hit: 1[W] + Strength modifier damage.

Armor-Piercing ThrustChar-op rank 0 is a 3rd level fighter attack power.

It is ineffective - although it is highly accurate, that bonus overlaps with other accuracy sources, and it doesn't do much damage (which is the only thing it does.)[1]