Armor Crush (Heavy Weapon Perk)

The bigger they are, the more there is to break. Repeated heavy blows buckle armor, ruin footing, and tear open their defenses.

When you hit a creature that is larger than you with a Heavy melee weapon, its Armor Class is reduced by 1 until the start of your next turn.

This effect stacks with each successful hit. Every additional Heavy weapon hit you land against that creature before the start of your next turn reduces its AC by another 1.