Acid Bolt

You hurl a bolt of acid at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d6 acid damage. If the target is wearing nonmagical metal armor, its armor is partly corroded and takes a permanent and cumulative −1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.

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