Thunderous Swarm

As a bonus action, you command a swarm of nanites to an unoccupied space within 30 feet of the caster. When you cast the spell, you can make a ranged spell attack against a creature within 10 feet of the swarm. On a hit, the target takes thunder damage equal to 3d4 + your spellcasting ability modifier.

As a bonus action, you can move the swarm up to 15 feet and target a creature within 10 feet of the swarm. On a hit, the target must make a Dexterity saving throw or fall prone.

When commanded the swarm supercharges its capacitors to unleash a thunderous bolt of sonic energy toward the target.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d4 for every slot level above 3rd. At 3rd level, the swarm has the option to cast the spell Thunder Clap, with a range of 5 ft. The targets make a Dexterity saving throw or fall prone.