Tasha’s Cauldron of Everything, pg. 115

Tasha's Caustic Brew

1-level Evocation

A stream of acid emanates from you in a line 30 feet long and 5 feet wide in a direction you choose. Each creature in the line must succeed on a Dexterity saving throw or be covered in acid for the spell’s duration or until a creature uses its action to scrape or wash the acid off itself or another creature. A creature covered in the acid takes 2d4 acid damage at start of each of its turns.
At higher levels: When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 2d4 for each slot level above 1st.