Half Tower Press

Save DC = 8 + your proficiency bonus + your Strength or Dexterity modifier (your choice)

If you take the Attack action on your turn you can use a bonus action to press your half tower shield into the fray.

Choose one creature of size Large or smaller within 5 ft. The target must make a DC Strength saving throw equal to your Save DC, on a failed save the target is Stunned. This effect ends at the beginning of your next turn.