Epicenter

Arcs of magical energy radiate and swarm around you in a 20-foot radius. Until the spell ends, this energy moves with you, centered around you. You choose either cold, fire, or lightning damage when you cast this spell. When a creature enters the spells area for the first time on a turn or starts its turn there, it must make a Dexterity saving throw. On a failed save, a creature takes 4d6 damage of the chosen type, or half as much on a successful save.

At higher levels: When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 per level above 3rd. And when you cast this spell using a spell slot of 5th level or higher, the radius increases by 10 feet per every two levels above 3rd.