Armor penetration
Armor penetration (often abbreviated as AP) is the amount of armor that an attack or spell ignores when calculating damage.
For example, an Air Magic spell that grants 25% armor penetration treats a foe with an armor rating of 80 as if it had only 60 armor, i.e. 80 - 25%*80. This would cause approximately ~41% more damage to the target than otherwise, since the increase in damage is dependent on the base armor rating.
There are two different types of armor penetration: base armor penetration and bonus armor penetration.
Base armor penetration[edit]
Base armor penetration is the non-stackable, fixed amount of penetration listed in a skill's description, e.g. "this attack has 20% armor penetration". If there is more than one source, only the highest value is used.
| Source | Penetration | Requirements/Notes |
|---|---|---|
 Strength |
1% per rank | When using attack skills |
 Air Magic spells |
25% | Each one that deals lightning damage |
| Penetrating Blow Penetrating Chop |
20% | |
 Penetrating Attack Sundering Attack |
10% | |
 Cruel Was Daoshen |
10% | Affects only Ritualist skills and only while ashes are held |
| Destructive Was Glaive |
20% | Affects only Ritualist skills and only while ashes are held |
| Destructive Was Glaive (PvP) |
10% | Affects only Ritualist skills and only while ashes are held |
| Sundering Weapon |
10% | |
 Spear of Lightning |
25% |
Bonus armor penetration[edit]
Bonus armor penetration is an additional amount of armor penetration, such as "armor penetration +20%". These do stack (adding them together) and add to the largest base armor penetration.
- Sundering weapon upgrades have a 10-20% chance to give attacks an additional 20% AP.
- Hornbows have an additional 10% AP on their attacks.
- Judge's Insight gives an additional 20% to attacks.
- The blessing Warrior's Might grants an additional 10% AP to attacks.
Notes[edit]
The armor provided by "I Am Unstoppable!", Illusionary Weaponry and Mantra of Signets is not reduced by armor penetration: it is only applied at the end of the armor calculation. As such, it is not counted in the bonus armor cap of +25.
Anomaly.Armor Penetration does not simply subtract the listed percentage of armor, sometimes it subtracts slightly more. The exact mechanics are unknown.
