Acid Trail

You magically coat your legs and feet in a slick, oil-like acid that is harmless to you. You gain 10 feet of extra movement, and whenever you move across solid ground, you leave a trail of acid in the spaces you’ve moved through. The acid lasts until the beginning of your next turn, and whenever a creature moves through a space with acid or ends its turn in one, it takes 4d4 acid damage and must make a Dexterity saving throw. On a failed save, the creature is knocked prone.

At Higher Levels. When you cast this spell using a spell slot of 4th-level or higher, the acid damage increases by 2d4 for each spell slot level above 3rd.