Conjure Volley

You fire a piece of nonmagical ammo from a
ranged or thrown weapon and hundreds of copies
and duplicates of the ammo fall in a volley from
above and then disappear.
Each creature in a 40 ft radius, 20 ft high
cylinder centered on a point within range makes
a Dex save. A creature takes 8d8 damage on a
failure, or half as much on a success. The damage
type is the same as that of the ammo used.