This is essentially a branch of Sergeant_Mark_IV's Brutal Doom V20b (Similar to Project Brutality). There are new enemy attacks, New weapons, a whole new character to play as, and more! If you find any bugs, you can DM me on ModDB, but if that isn't possible, DM me on twitter @BackupMengo
This looks great, dude. The idea of different types of slugs for shotguns sounds great. In addition, the idea of a weapon that fires high-voltage electricity rays also sounds good. Regarding the recoil of each of the shotguns when they are fired, I think it's too much; the recoil should be reduced a little. That would be all for now.
I was going to add alternate ammunition for bullets and cells too but coming up with ideas for those were really annoying and the shotguns and explosives were annoying enough to code so I drew the line at that.
The lightning gun is actually from quake, and the sprite and functionality are by ⋆Ƅarge™.
About the shotguns, most of the time when firing a shotgun, players would usually be on the ground, I think it also adds a bit of depth, thinking of trading some ammo for a boost, like losing health and ammo to rocket jump, but I understand what you mean.