Promote to Captain

You use shields not just for protection but also for offense. You gain the following benefits while you are wielding a shield:

Shields you wield count as proficient Melee Weapons, with the Heavy property, and use your Strength modifier for attack and damage rolls. They deal 1d6 bludgeoning damage, piercing damage if the shield has the spiked property, or slashing damage if the shield has the bladed property. 

Magical shields may add their defense bonus to attack and damage rolls, if it is used as a weapon.