Blood Boil

You can manipulate the blood flow of any creature you see. The targeted creature takes an extra 3 damage on the next attack that is made against it. Make a ranged spell attack against the target. On a hit, the target takes 1d10 necrotic damage.

The spell does more damage when you reach higher levels: 2d10 at 5th level, 3d10 at 11th level, and 4d10 at 17th level.