Tide of Iron (5e Feat)

You have trained with your shield until it is a dangerous weapon in its own right.

Shields are no longer treated as improvised weapons for you, and you are considered proficient whenever you attack with a shield.
When you make a bonus attack by two-weapon fighting, you can add your Strength modifier to the damage of the bonus attack if that attack is made with a shield.
If your shield is magical, you add its magic bonus to attack and damage rolls as though it were a magic weapon. For example, a +1 shield would grant a +1 bonus to attack and damage rolls when attacking with the shield.
When you take the Attack action and make an attack with a shield you are holding in one hand, you can use a bonus action to make an attack with a weapon in your other hand.