Corrosive Blade (HB)

As an action you imbue the weapon with the spell’s effect and make one melee attack with it against a creature within melee range of you. On a hit, the target suffers the weapon's normal effects plus 1d8 acid damage, then starting at 5th level the target must make a Con Save taking an extra 1d8 poison damage or half on a success.

This spell’s damage increases when you reach certain levels. At 5th level (2d8 acid) (1d8 poison), 11th level (3d8 acid) (2d8 poison), 17th level (4d8 acid) (3d8 poison).