Calamity (CZ75): More Damage, Larger Mag, More Reserve Ammo, Becomes Fully Automatic
Calamity & Jane (CZ75 Dual Wield): Same as above
Mustang & Sally (M1911): Dual Wield, Fires Grenades, Smaller Mag, Smaller Reserve, faster reload time, slower rate of fire, lots more damage
Cobra (Python): More Damage, larger mag, more reserve, speed reloader
AUG-50M3 (AUG): More Damage, More reserve, Masterkey that reloads 2 shells at once
Predator (Commando): More Damage, larger mag, more reserve, dual mag
G16-GL35 (Famas): More Damage, Larger mag, more reserve, red dot sight
EPC WN (FN FAL): More Damage, 3 round burst, reflex, more reserve, larger mag
G115 Generator (G11): More Damage, More reserve, becomes automatic, sway on low power is nothing
Lamentation* (Galil): More Damage, More reserve, Red dot sight (sometimes)
Mnesia (M14): More Damage, Larger mag, more reserve ammo, grip
Skullcrusher (M16): Noobtoob, fully automatic, more damage, more reserve
AK-74fu2 (AK74u): More Damage, larger mag, more reserve, red dot sight, nice name
MP115 Kollider* (MP5K): More Damage, Larger mag, more reserve
Afterburner* (MP40): More Damage, Larger mag
MPL-LF (MPL): More Damage, Larger mag, more reserve, red dot sight
Toyko & Rose (PM63): Dual wield, more damage, more reserve, larger mag
Phantom (Spectre): More damage, larger mag, reflex sight, faster reload, more reserve
H115 Oscillator (HK21): More reserve, More damage, larger mag
R115 Resonator (RPK): More damage, more reserve, larger mag
D115 Disassembler (Dragunov): Variable Zoom, more damage, more reserve
L115 Isolator (L96A1): More reserve, Variable Zoom, Larger mag, more damage
Typhoid & Mary (HS10): Dual Wield, More reserve, larger mag, more damage, faster reload
Hades (Olympia): More damage, Dragon’s Breath, More reserve, quicker reload
SPAZ-24 (SPAS-12): More damage, larger mag, more reserve, reloads all in one shell, automatic
Raid (Stakeout): More damage, longer range, larger magazine, more reserve, reloads 2 at a time, grip
China Beach (China Lake): More damage, larger mag, no ADS, faster pump action, reloads all at once, more reserve, higher mobility
M72 Anarchy (M72 Law): More Damage, Semi-automatic, higher mobility, no ADS, larger “mag”, More reserve
Krauss Refibrillator (Ballistic Knife): More damage, increase melee damage(add a bowie knife to it to enlargen it even more), more reserve, quicker reload, shoot a player to revive them instantly
Awful Lawton (Crossbow): more damage, longer time to explode, crossbow bolts attract zombies towards it, kills about 6 zombies max
Porter’s X2 Ray Gun (Ray Gun): More damage through multipliers, larger mag(x2), more reserve, sight changes colors(I only know red, yellow and blue, maybe more)
Zeus Cannon (Thunder Gun): More damage, larger splash radius, larger mag, more reserve ammo
Winter’s Fury (Winter’s Howl): More Damage, larger mag, freezes more zombies, 1st shot slows down speed, 2nd freezes zombies in ice
Hope this helps