Wall of Acid

You create a wall of acid on the ground at a point you can see within range. You can make the wall up to 30 feet long, 10 feet high, and 1 foot thick, or you can make a ringed wall up to 20 feet in diameter, 20 feet high, and 1 foot thick. The wall vanishes when the spell ends. The wall’s space is difficult terrain and any creature that enters and starts it's turn in the wall must make a Constitution saving throw on a failed throw take 5d6 acid damage half as much on a successful one.

Any ranged weapon attack that enters the wall’s space disintegrates unless the attack rollwas 18 or higher, and poisen and acid damage is absorbed unless the attack roll was 18 or up.