Acidic Bag of Bearings

As an action, you can spill the 1000 acidic metal
balls from their pouch to cover 10 sq. ft. area. A
creature moving across the area must succeed on
a DC 13 Dexterity saving throw or fall prone and
suffer 4d4 acid damage.
Alternatively, you may sling the contents at a
creature within 20 feet. They must succeed on a
DC 16 Dexterity saving throw or take 4d4 acid
damage, or half as much on a success. Terrain
in their space and all adjacent space becomes
difficult terrain for 1 minute. R