Hello!
I have collected all special weapons.


ACT I: SET FIRE TO THE FACE ON FIRE
Red
- Special Weapon: Primitive Shotgun (special0)
Yellow
- Special Weapon: Twin Flux Rifle (special3)
Blue
- Special Weapon: Autogun (special1)
Green
- Special Weapon: Disintegrator Beam (special2)
ACT I End
- Special Weapon: Cyclone Cannon (special4)

ACT II: THE PERILS OF BELIEVING IN ROUND SQUARES
Red
- Special Weapon: Frag Launcher (special5)
Purple
- Special Weapon: Shredder Rifle (special6)
Blue
- Special Weapon: Incinerator (special8)
Yellow
- Special Weapon: Twin Autocannon (special7)
ACT II End
- Special Weapon: Stinger Cannon (special9)

ACT III: DIVINE FILTH
Blue
- Special Weapon: Electrocution Rifle (special10)
- Special Weapon: Scorcher (special11)
Green
- Special Weapon: Gattling Cannon (special12)
- Special Weapon: Heavy Plasma Rifle (special13)
ACT III End
- Special Weapon: Gauss Cannon (special14)

ACT IV: HEAD WOUND CITY
Round 1:
- Special Weapon: Lightning Chaingun (special15)
Round 2:
- Special Weapon: Frostburner (special16)
Round 3:
- Special Weapon: Ion Slug Cannon (special17)
Round 4:
- Special Weapon: Super Shotgun (special18)
Round 5:
- Special Weapon: B.F.G. (special19)