Acid Paint

You conjure a sticky acid coating covering a point of your choice within range. The paint is difficult terrain, can be any shape no larger than 10 square feet, and lasts for the duration. Any creature that starts its turn in the paint takes 2d4 acid damage from the fumes. Any object with an AC less than 15 that is not being worn or carried dissolves at a rate of one inch an hour while in contact with the paint.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the spell creates thicker paint, increasing the amount of damage by 2d4, the AC threshold by 1, and the dissolving speed by 1 inch per hour, for each slot level above 1st.