And without further ado, I present to you:
Guns Tetrakaikimbo Akimbo.
Disclaimer: This is spammy as all hell.
Additional disclaimer: The shells noticeably fly out in your face. I didn't want to move the shell casing exit point from the spot that it resides on the Tetrakaikimbos, the Akimbos, and the normal gun, but in this one it shoots the shells kind of in your face.
One more disclaimer: It turns out the Tetrakaikimbos normally have an icon, but the .cs file checks for the icon in the wrong place. I opted to continue this error for consistency reasons.