Conjure Barrage (reworked)

You throw a nonmagical weapon or fire a piece of nonmagical ammunition into the air to create a cone of identical weapons that shoot forward in a 60 ft. cone and then disappear. When you cast this spell, you can designate certain creatures. Each non-designated creature in the area must make a Dexterity saving throw, taking 3d12 damage on a failed save, or half as much damage on a successful save. The damage type is the same as that of the weapon or ammunition used as a component. 

At Higher Levels. When you cast this spell using a spell slot of 4th or higher level, the damage increases by 1d12 for each slot level above 3rd.