Recently, I had watched the anime Fate: Stay night, and within that show, the archer had the ability to shoot an arrow and have a volley of arrows rain from the sky. It was pretty dope! I wanted to recreate it, so i did within 1.12. It worked, everything was cool, and i had a lot of fun with it. Problem is, a lot of other cool commands were added in 1.13, and with the updated command system, I'm totally funked. I haven't been able to crack it at all. So thought you guys might have the answer!
So how i got it to work in 1.12 was by creating a unique arrow (duration, effect, etc), having a command block tag it as soon as it entered the air, and then summon arrows as it flew.
Like I said, this command set worked within 1.12, but I have no idea how to translate it over into 1.13. I would really appreciate your help! And just btw, the characteristics of the arrow (Id, duration, amplifier) were completely randomized, so don't feel obligated to use the same characteristics or anything! Also, forgive my messy code. Its basically Frankenstein's monster (little bit of command from one, little bit of command from another) Thanks!