Corrosive Blade

As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell’s range, otherwise, the spell fails. A pale green acid rushes down the blade of the weapon and on a hit, the target suffers the attack’s normal effects as well as becoming afflicted with acid. On the start of the target's next turn, it suffers 1d4 acid damage.

At Higher Levels. When you cast this spell at the 5th level, the melee attack deals an additional 1d4  acid damage on hit. This damage increases at the 11th and 17th levels by 1d4 acid damage. Targets that are coated in acid take an additional 1d4 of acid damage on the start of their next turn at the 5th level, which increases by an additional 1d4 at the 11th and 17th levels.