GrandmasterD hasn't done the math yet and I'm an impatient ****abish, so I'll do the math for him. For the sake of simplifying things, only marks will be considered. 9x Greater Mark of Armor Penetration gives 1.28 * 9 = 11.52 armor penetration

Recall that:

• Damage multiplier = 100 / (100 + Armor - Armor Penetration)
• Therefore, raw damage needed to deal 100 physical damage to the target = 100 / (Damage multiplier) = 100 + Armor - Armor Penetration

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