Wren's Voltaic Jolt

A spark of arcane energy streaks towards a creature or object within range. Make a ranged spell attack against the target. You have advantage on the attack roll if the target is made of metal, or wearing armor made of metal. On a hit, the target takes 1d8 lightning damage.

The spell's damage increases by 1d8 when you reach 5th level (2d8), 11th level (3d8), and 17th level (4d8).