DISCLAIMER: The information in this article is based on experimental research conducted by the community, and may contain inaccuracies and speculation. While we strive for accuracy in these articles, we make no claims of experimental rigor or unbiased conclusions. Caveat lector.
Consider the following situation: a level 20 elementalist with 15 air magic uses Lightning Strike against a warrior wearing Gladiator's Armor (and not wielding a shield). Lightning strike has 25% armor penetration and the warrior has 80 AL versus elemental damage, which results in an effective 60 AL (80 * (1 - 0.25)). Against an effective 80 AL, lightning strike would have dealt 35 damage, but armor penetration will increase the damage to 501. This is roughly a 43% increase.
There are two sources of armor penetration, base armor penetration and bonus armor penetration:
- Base armor penetration is a set armor penetration value which is usually listed in game with text such as "this attack has 20% armor penetration." Base armor penetration does not stack, and only the largest value is used for any single hit. Sources include:
- Bonus armor penetration is an additional armor penetration value which is usually listed in game with a preceding plus sign, such as "+20% armor penetration." Bonus AP does stack with base AP and other sources of bonus AP. Sources include:
1 see Damage for additional information on damage calculations.