Is it possible to implement a gun in the game?

[dezgasting]

This time around, I want to create Jhin from League of Legends. 

However, I already ran into a problem even before starting out -- I have no idea if it's possible to implement a very specific working gun in the game.

So, let me describe what I want:

Jhin in canon has a magical handcrafted gun. It shoots magic bullets (duh), which usually blow up in a form of a lotus flower upon hitting the target, though I don't think I'll be implementing it any time soon. It's not what's the problem is at the moment. 
The problem is in those damn bullets. He shoots four bullets before he needs to reload; and the fourth always deals more damage (crits), grands him a movement speed boost and, well, makes him yell "FOUR!". Yet I am not sure if there's any way to implement a gun (in the first place), that shoots four times before needing to reload, and that crits at fourth (and possibly grants movement speed burst, though with the way the game works and monsters getting little stagger upon getting hit, I don't think this will be needed). Oh, and he must yell "four" (almost) every fourth shot. Jhin that doesn't yell "FOUR" everytime is not Jhin.
...don't ask why.

This I consider mandatory adding, since his character is all about being obsessed with the number 4, and his gun is one of his most important aspects as a character. 

And I just have no bloody clue which mod's code (that at least has a gun) can I look up and study. All I found was DST gun mods. 

Is it even possible? Or should I just abandon the idea of adding Jhin to the game as a playable character?

I mean, I could go with just his lotus traps that I have a few ideas on how to add, but I just feel like Jhin without his 'Whisper' (the name of the gun) is not Jhin. 

[myxal]

Do you have the Hamlet DLC? Wheeler's Pew-matic horn (prefab: trusty_shooter) should be pretty close to what you're looking for.