Acid Sphere

A black sludge oozes from your pointing finger to a point you choose within range and then transforms with a slow whistle into an explosion of corrosive acid. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 8d6 acid damage on a failed save, or half as much damage on a successful one.

The acid leaves a trail behind it as it travels. The trail stays for one round, and if any creature walks through the trail, voluntarily or involuntarily, they take 1d6 acid damage.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage for the acid ball increases by 1d6 for each slot level above 3rd.