You summon Zeus onto the playing area near you. He serves as a protector and helper. Each round he is active he can fire up to 10 lightning bolts at the desired characters or monsters.

A target must make a Dexterity saving throw. The target takes 4d20  lightning damage on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher,  Zeus stays for one additional round, and his lightning does an additional d20 for each spell slot level above 4.