Armor penetration

Armor penetration refers to the amount of an opponent's AL that will be ignored when calculating damage from a single damage-dealing attack or skill.

To illustrate, an attack that has 25% armor penetration against an opponent with 80 AL will give him an effective 60 AL (80 - 25% * 80) against that attack. If the attack would have caused 20 damage against the original 80 AL, armor penetration will increase the damage to 28 (roughly 20 &times; sqrt(2); see the damage article for the explanation). Note that this is a 40% increase in damage &mdash; armor penetration and the damage increase are not linearly related. (This is a common misconception.)

Note: Armor penetration is more effective against higher AL, but still strong against lower AL.

Sundering weapon upgrades increase the armor penetration of the corresponding weapon attacks (with some probability).

Related Skills
These skills cause armor penetration:


 * Prophecies Campaign
 * [[image:Warrior-icon.png|15px]] Penetrating Blow
 * [[image:Ranger-icon.png|15px]] Penetrating Attack
 * [[image:Monk-icon.png|15px]] Judge's Insight
 * [[image:Elementalist-icon.png|15px]] Chain Lightning
 * [[image:Elementalist-icon.png|15px]] Enervating Charge
 * [[image:Elementalist-icon.png|15px]] Lightning Javelin
 * [[image:Elementalist-icon.png|15px]] Lightning Orb
 * [[image:Elementalist-icon.png|15px]] Lightning Strike
 * [[image:Elementalist-icon.png|15px]] Lightning Touch
 * [[image:Elementalist-icon.png|15px]] Mind Shock
 * [[image:Elementalist-icon.png|15px]] Shock
 * Factions Campaign

Research Questions
It is currently a matter of dispute how armor penetration interacts with armor ignoring skills. Specifically, the dispute rages over the skill Judge's Insight, which is claimed to cause holy damage (a purportedly armor ignoring damage type) and 20% armor penetration. Empirically, it has been observed that this skill does not in fact ignore armor, so the qustion is currently moot.

Theoretically, there are many possibilities. Armor ignoring damage sets the AL to be equal to the DL to give a net armor effect of 1 (see the damage article for the details).
 * Armor penetration can reduce a fraction of this effective AL, i.e., set the effective AL to be 0.8 &times; DL; or
 * It can set the effective AL to be (DL - 0.2 &times; base AL); or
 * It can simply be overridden by the armor ignoring feature, i.e., set the effective AL to be equal to the DL.

If the behavior of Judge's Insight is ever changed to make it consistent with other holy damage skills, then we might find a way to settle this dispute.