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Armor penetration (sometimes abbreviated ArP) is a number typically appearing on items that indicates the amount of armor ignored by an attack. Some abilities, enchantments, items and spells can contribute bonus armor penetration also (the bonus spell usually has the name "Armor Penetration^{ω τ α} X").

ArP can be found as both abilities (ex. sunder armor), or as passive statistical upgrades found on equipment pieces (ex. Season 3 PvP armor).

• reduces the amount of armor that your target has against melee attacks.

• has a greater effect on lower level targets, and also has a greater benefit the more ArP you possess.

Examples; 1k penetration is a 5.7% increase on an 8k armour target, 6.8% increase on a 5k armour target, 7.9% increase at 3k armour and a 9.5% increase at 1k armour.

This also illustrates how Armour Penetration has increasing returns with itself. Going from 2k ArP to 2.5k ArP nets the same increase as going from 1.5k ArP to 2k ArP, but going from 1.5k to 2k PEN is a higher increase than going from 1k PEN to 1.5k pen.

Sometimes confused with "spell penetration".

Patch changes

• As of Patch 2.4.1, Armor Penetration will now display on the character sheet (Armor Penetration displays in the hit rating section).

See also

• Formulas:Armor penetration