Ring of Corrosion

1-level Evocation

Each creature in a 15-foot cube originating from you must make a Dexterity save. On a failure, a creature takes 2d8 acid damage. On a success, the creature takes half damage.   The ground within range of the spell becomes eroded by the spell and is treated as difficult terrain for the duration of the encounter.
At higher levels: The damage increases by 1d8 for each slot level above 1st.