idk if its exactly what you want but i think its pretty cool

Code (Skript):

1. on script load:
2.     create shaped recipe with result snowball named "Rain of Arrows" using arrow, arrow, arrow, arrow, feather, arrow, arrow, arrow, and arrow
3.  
4. on projectile shoot:
5.     if name of shooter's tool is "Rain Of Arrows":
6.         set metadata "Arrow" of projectile to "Rain of Arrows"
7.         wait 10 ticks
8.         if metadata "Arrow" of projectile is "Rain of Arrows":
9.             delete projectile
10.             pop ball firework colored red at projectile
11.             spawn a arrow at projectile's location
12.             spawn a arrow 0.5 meters right of projectile's location
13.             spawn a arrow 0.5 meters left of projectile's location
14.             spawn a arrow 0.5 meters in front of projectile's location
15.             spawn a arrow 0.5 meters behind projectile's location
16.  
17. on projectile hit:
18.     if metadata "Arrow" of projectile is "Rain of Arrows":
19.         clear metadata "Arrow" of projectile
20.         delete projectile