Arrow Army

 The piece of ammunition is multiplied as it flies through the air. The pieces of ammunition speed up and spread out to cover an area within a 100 ft radius of a point within range. Whatever is the target ( this is considered the first ring) takes three times damage and is automatically hit, anything within the first 25 ft (this is the second ring) is automatically hit and takes 1.5 times damage, anything between 25-50 ft (this is the third ring) is automatically hit, anything between 50-75 ft (this is the fourth ring) has an option to make a dexterity saving throw (DC 25) on a failed save the attack deals 1.5 times damage and on a successful save it deals .75 damage and if something doesn't make the saving throw it is automatically hit, and anything in the final 25 feet (this is the fifth ring) must make a dexterity saving throw (DC 18) on a failed save the target takes full damage and on a successful save they take half damage. 

 The attack deals 16 piercing damage and 8 bludgeoning damage on a hit with a arrow, and it deals 12 of some type of damage instead of the piercing damage if not used with arrows this damage is considered to be from magical, silvered, and adamantine weapons for game purposes as well as turning any immunities to piercing or bludgeoning damage into resistances for this attack only. If arrows are used you can alternatively sacrifice one of the rings of arrows to move the other rings up one ring. For example if the last 25 ft are sacrificed then the radius is only 75 ft, but each ring takes the effect of the ring before it, and the first ring just doubles in damage. Only four of the rings can be sacrificed, and the sacrificed ring always has to be the outer ring. After this spell is cast whatever was within its area becomes difficult terrain, and a creature that moves through the area at any point on its turn must make a dexterity saving throw, on a fail the creature takes 1d6 piercing damage that is silvered,adamantine, and magical for game purposes.