Acidic Blood Salve

You brandish the weapon used in the spell’s casting and as a Bonus Action slide your hand along the blade creating a dark crimson blood which coats the weapon for a number of successful attacks equal to your Proficiency bonus. These attacks deal an extra 1d8 Acid damage. 

This spell’s damage increases when you reach certain levels. At 5th level, the melee attack deals an extra 2d8 acid damage to the target on a hit, at 11th level 3d8, and 17th level 4d8.