Aivoc's Voltaic Serpent

A serpent of lightning flies out of your hands, arcing through creatures it can reach. The serpent is immune to conditions, opportunity attacks, and damage, as it traverses a distance equal to the spell's range starting from you. Its path can turn at any point in any direction. Any creature it passes through on its movement make a Dexterity Saving throw, taking 8d6 lightning damage on a failure, or half on a success. The serpent can pass through and damage the same creature up to twice, provided it arcs through 3 other creatures first.

Once the serpent has traversed all its movement, or your turn ends, it disappears.

At Higher Levels. You increase the serpent's travel distance by 20ft for each higher level.