The Death Coil

Fire a blast of unholy energy at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d10 necrotic damage. If you target an undead creature you gain 1d6 health as well. 

This spell's damage increases by 1d10 when you reach 5th level (2d10), 11th level (3d10), and 17th level (4d10). The amount of temporary health gained increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).