Volt blast

A bright flash of electricity arcs from you to a point you choose within range and then explodes in a blast of electricity. Each creature in a 10-foot-radius Sphere centered on that point makes a Dexterity saving throw, taking 4d8 Lightning damage and having the paralyzed condition on a failed save or half as much damage only on a successful one.The creature makes the saving throw at the end of each of its turns, ending the effect on itself on a success. The Paralysis can last a maximum of 5 rounds.

Using a Higher-Level Spell Slot. The damage increases by 1d8 for each spell slot level above 3.