Azure Shieldbash

You conjure a glittering disc of sapphire energy upon the surface of your shield or in your hand. Make a melee weapon attack against a creature within range. On a hit, the target suffers the weapon attack's normal effect, takes 1d4 force damage and your AC is increased by 2 until the start of your next turn. If a creature hits you with an attack, the shield shatters, and the increase to your AC ends.

The spell's damage increases by 1d4 when you reach 5th level (2d4), 11th level (3d4), and 17th level (4d4)