Vincent's Sparkbolt

You hurl a lightning-infused bolt at a target within range. Make a ranged spell attack. On a hit, the target takes 3d8 lightning damage and the bolt is embedded in it. On your future turns, you can use an action to cause the target or one creature within 10 feet of the target to take 3d8 lightning damage. The spell ends if you use your action to do anything else.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the damage is increased by 1d8 per slot level.