Shield Bash Mechanics

Attacking

You may attack with your shield in your main hand using the Attack action, or in your off-hand using your Bonus Action. Attacking with a shield always uses your Strength in the Attack Roll and you do not add any modifiers to your damage rolls unless you possess the Shield Bash feat. When shield bashing you lose your shield bonus to Armor Class unless you possess the Shield Bash feat as well.

Damage

Armguard: Strength -1
Shield: 1d4
Heavy Shield: 1d6

*The feat Shield Expert increases the damage of these by one step.*