Thundersnap

You create a burst of thunderous sound that can be heard up to 100 feet away and a visible rupture of sound that streaks toward a creature. The target takes 1d6 damage. If you get a critical hit with this spell attack you deal maximum damage on your damage dice instead of rolling (meaning that you would deal 12 damage) on a critical hit. 

The spell’s damage increases by 1d4 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).