The Glock (retextured model from Counter-Strike) is named "9x19mm Sidearm" in game. It is the starting weapon of the terrorist faction.
Heckler & Koch USP45 Tactical
The USP returns from Counter-Strike and named "KM .45 Tactical Pistol" in game. It is the starting pistol for the counter-terrorist faction and comes with a detachable silencer.
SIG-Sauer P228
P228 is the same model from Counter-Strike and is called ".228 Compact" in game. Fires .357 SIG rounds.
IMI Desert Eagle Mark XIX
Named "Nighthawk .50 C" in game. Appears as the most powerful sidearm in the game. Its model is almost identical to Counter-Strike Source. The weapon comes with a gold-plated variant and an akimbo variant which is only available in Zombie modes.
FN Five-seveN
Named "ES Five-Seven" in game, a weapon exclusive to the counter-terrorists. The model is from Counter-Strike.
Beretta 92G Elite II
Named ".40 Dual Elite" in game. Probably a homage to John Woo or Chow Yun Fat. The dual pistols are purchasable by the terrorists. The model is the same as in Condition Zero.
Colt Anaconda
Named simply "Anaconda" in game and fed with seven .50 AE rounds. Appears as the only revolver in the game and is statistically equal to the Desert Eagle.
SVI Infinity
The Infinity comes with some color variants and three akimbo configurations. Appears as the most diverse weapon and the most accurate pistol in the game. The akimbo variants have secondary firing mode which does high rate of fire like the SMGs, although it's extremely inaccurate.
Luger P08
named "Luger" in game, it also comes with gold and silver finishes. It is the most powerful 9mm caliber pistol in the game, but its low capacity and not very accurate. It's the one of four WW2 classic weapon in the game. The Silver Luger is only available in Zombie Mode 3 and usable by Blair only. It is effective against zombies due to its high knock-back power.
Flintlock Pistol
An unknown model of Flintlock pistol is available in the game. With this weapon the player can kill an enemy with one shot.
MP-412 REX
The MP-412 REX appears in the game is called "Skull-1". It's a break-frame double-action revolver designed for anti-zombie purposes and available to fire in "sharpshooting mode" or "burst firing mode".
AMT Automag V
Named "Automag V" in game. Currently appears as a skin for the Desert Eagle. Still available only in Korean version of CSO.
Shotguns
Benelli M3
The M3 is returned from Counter-Strike and named "Leone 12 Gauge Super" in game. It is the cheapest shotgun in the game and suitable for close-quarter battle.
Benelli M4 Super 90
The XM1014 (using Condition Zero model) is named "Leone YG1264 Auto Shotgun" in game. It does lower damage but has the highest rate of fire than any other shotguns.
USAS 12
A fully automatic shotgun with a 20-round drum magazine which available for the terrorists only. It's very powerful in close range but it's unstable. Comes with a variant called the "USAS12 Camo". This variant does higher damage, lighter and has higher rate of fire, suitable to use in Zombie modes.
Winchester Model 1887
Named "Winchester" in game. It is very effective for hunting zombies and has high knock-back power. The weapon also comes with a gold-plated variant which could fed with 9 round and have 36 rounds spare ammo.
Sawed-off Double Barreled Shotgun
An unknown model of sawed-off double barrel shotgun. It does high damage even in middle-range although it has the lowest capacity. It's also the weapon which has the highest knock-back power in the game. There's a variant called the "Quad Barrel". The "Quad Barrel" is a shotgun with four barrels, it's only available in Zombie mode 3 and usable by the heroine only. The Quad Barrel could fire 4 shells each time when the user hold on the secondary fire key.
Kel-Tec KSG
The Kel-Tec KSG 12 gauge is fed with 15 rounds in game. It's very effective at close range.
The SPAS-12 in game is a pump-action shotgun. Comes with two variant called the "SPAS-12 Deluxe" and "SPAS-12 Cobra" which has semi-automatic firing abilities.
Submachine Guns
Steyr TMP
Named "Schmidt Machine Pistol" in game. It is a low cost sub-machine gun with an integrated suppressor for the counter-terrorists. Model is from Condition Zero.
Ingram Mac-10
Unlike most of other guns, the MAC-10 retains its name because the company holding the rights to the name went bankrupt. It's the same level as the TMP, as the low cost sub-machine gun for the terrorists faction. The weapon model is from Counter-Strike.
Heckler & Koch MP5A5
The MP5 is returned from Counter-Strike (with different front sight) and named "KM Submachine Gun" in game. Appears as the most flexible sub-machine gun in the game. It comes with a "Chinese Year Edition" and a gold-plated variant. These variants have higher knock-power than the original weapon.
Heckler & Koch UMP
Named "KM UMP45" in game. Appearing to filled the lack of firepower of the MP5. It's a weapon from Counter-Strike. The weapon also comes with a Anti-zombie variant which called the "Skull-3".It is chambered in .45 Anti-Zombie rounds and featured with an 35 round mag, Aimpoint M2 Scope, undetachable suppressor and also can be dual-weilded.
FN P90
The P90 is returned from Counter-Strike named "ES C90" in game. It has high penetration power and also high capacity but it does low damage and is expensive. It also comes with a "Chinese Year Edition". The model is the original Counter-Strike P90 with front ripped from Counter-Strike Source model.
Heckler & Koch MP7A1
The MP7A1 in game can switch between "pistol mode" and "SMG mode". Appears as the most compact SMG in the game. But It is only fed with 20 rounds magazine. The weapon comes with a high-capacity variant called the "MP7A1 60R" which fed with 60 rounds and a akimbo variant which only available in Zombie modes.
SA Vz.61 Skorpion
The SA Vz.61 Skorpion appears heavily modified in game and renamed into "Kart Blue" and "Kart Red". Both of them can switch between "SMG mode" and "rifle mode". The Kart Blue was belong to the Counter-terrorists faction, and the Kart Red was belong to the terrorist faction. These weapons are both belong to the rifles category.
Daewoo K1A
A Korean Carbine classified as SMG in game which available for the counter-terrorists faction only. It has similar firepower and high rate of fire which equal the assault rifles. It can also effect at long range. It has a Dragon painted variant called the "K1ASE" which does higher damage, rate of fire and better accuracy.
M1928 Thompson
Named "Thompson Chicago" in game. Also comes with a gold plated variant. It's powerful and has high capacity, also has lower price than many SMGs. It's also the one of four WW2 classic weapon in the game.
TDI Vector
Named "Kriss Super V" in game, comes with a detachable suppressor and an akimbo configuration. Its firepower is equal to the UMP45 and the Thompson. Although it's cheaper, low recoil and accurate.
Assault Rifles
AK-47
The AK is returned from Counter-Strike and named "CV-47" in game. As the most reliable rifle for the terrorists faction. It's powerful and cheap, but inaccurate when fired fully-automatic. It comes with a gold-plated variant and a "special dragon edition" which can perform "speed reloading". In zombie modes gameplay, the High-capacity variant of the AK is also available. It is fed with 60 rounds magazine and equipped with a scope, also it does very high damage against zombies and has high rate of fire. The model is the original CS AK with front ripped from Source.
IMI Galil ARM
The Galil is returned from Counter-Strike and is named "IDF Defender" in game. Has the stats of the 5.56x45mm variant. This weapon is available for the terrorists faction only and is the cheapest rifle in the game. It is very effective in close and middle range. It has Condition Zero model on original Counter-Strike animations.
FAMAS
Renamed as "Clarion 5.56" in game, it is the cheapest rifle for the counter-terrorists faction. It's able to fire in 3 round burst, has low recoil and also high rate of fire. Retextured model from Counter-Strike.
SIG SG552 Commando
Named "Krieg 552" in game and available for the terrorists faction only. Appears as the assault rifle with the highest rate of fire. Effective in close and middle ranges. An original Counter-Strike model with Condition Zero scope.
Steyr AUG
Renamed "Bullpup" in game. Available for the counter-terrorists faction. Appears as an assault rifle which equal the SG552. It has high rate of fire and good accuracy. Effect in middle range to long range. It's a weapon from Counter-Strike.
Colt M4A1 Carbine
The M4A1 is returned from Counter-Strike and named "Maverick M4A1 Carbine" in game, comes with variations that all feature a detachable suppressor (except the Camouflaged M4). It is the most reliable rifle for the counter-terrorists. This rifle is accurate, powerful and inexpensive, effective in any ranges. The Camouflaged M4A1 is equipped with a scope. The gold-plated variant has a foregrip and tactical light installed. The M4A1 Dragon has "speed reloading" feature. Model is ripped from Counter-Strike Source.
Heckler & Koch XM8
The XM8 in game can be convert freely between the carbine variant and the sharpshooter variant, as the new generation rifle for the terrorists faction. It has high rate of fire and light weight, although it's not accurate.
FN SCAR
The FN SCAR in game can be convert freely between the SCAR-L and the SCAR-H. It's available for the counter-terrorists, as a new rifle for the counter-terrorists. The SCAR L has higher rate of fire and accuracy, effect in middle range. The SCAR H is powerful but low capacity, heavy, mostly effect at close range.
Mk 14 Mod 0 EBR
Named "M14 EBR" in game. Appear as the most powerful assault rifle in the game. The rifle is accurate when single-fire, but it's heavy and has low rate of fire. It also comes with a Anti-Zombie sniper rifle variation which called "Skull 5", the rifle fires 5.56 Anti-Zombie round and fed with 24 rounds.
FN F2000
Named simply as "F2000 in game. It's the most low recoil rifle in the game. Comes with a zoomable scope.
IMI Tavor TAR-21
Named simply as "TAR-21" in game. Comes with a EOTech telescope. This rifle has high rate of fire but low recoil, and has high knock-back power against zombies.
M16A4
The M16A4 retains its name in game. Painted with desert camo and installed a forearm. It is only available for the counter-terrorists faction. The weapon is only be able to fire in 3 round burst. It's effect in middle range battle.
AN-94
The AN-94 retains its name in game. It is only available for the terrorists faction. The weapon's only be able to fire in 2 round burst. It's very accurate and effect in middle range.
Sturmgewehr 44
The StG44 is now available in the game, as the first assault rifle in the world. The rifle is powerful as the AK but it's very unstable and low rate of fire.
QBZ-95B
The QBZ-95B is a shorten barrel assault rifle based on the QBZ-95 which could fed with 35 rounds mag in game. This weapon is available in Korean, Taiwan/Hong Kong and China CSO only.
HK 416
The HK 416 retains its name in game. Currently appear as a skin for the M4A1. Still available only in Korean version of CSO.
AKM
The modernized AKM retains its name in game. Currently appear as a skin for the AK-47. Appears as a black furniture. Still available only in Korean version of CSO. It features a synthetic buttstock, pistol grip and handguard which similar to the AK-103.
Enfield L85A2
Named "L85A2" in game. Currently appear as a skin for the FAMAS. Still available only in Korean version of CSO.
FN FNC
Currently appear as a skin for the Galil. Still available only in Korean version of CSO.
Machine Guns
M249 PARA SAW
The SAW is returned from Counter-Strike and retains its name in game. It's suitable used for cover teammates in front line. It comes with a Anti-Zombie variant called the "Skull-7". The Skull-7 is chambered with 120 rounds of 5.56 Anti-Zombie cartridge and equipped with a zoomable scope. It has its front ripped from CSS model and positioned too high.
QBZ-95
The QBZ-95 is fed with a 75 round drum magazine, appears as the "QBB95" and belongs to the MG class in game. This MG has similar features as the assault rifles and also has cheap price. It comes with a high-capacity variant called the "QBB95EX". This variant is fed with 80 rounds and with 400 rounds spare ammo, suitable to use in zombie modes.
MG3
The MG3 retains its name in game. Comes with 200 round ammunition box. It's very effect in zombie modes due to its high rate of fire and suppression power.
GE M134 Minigun
The GE M134 Minigun is named simply as "M134" in game. Comes with 200 round belt. It has the highest rate of fire than any other MGs. But it needs 1.5 seconds static time before you fire it. It comes with a modified variant which could reduce the static time.
Heckler & Koch HK23E
Named simply as "HK23" in game. Comes with 100 round ammunition box. It has high flexibility and effect for engage the zombie bosses in Zombie Scenario Mode. It comes with a gold-plated variant.
M60E4
The M60E4 retains its name in game. Comes with 100 round ammunition box. It is powerful and has high flexibility, but it has lower rate of fire.
Heckler & Koch MG36
The MG36 retain its name in game. As the most flexibility machine gun in the game. Comes with 100 round C-MAG drums and a zoomable scope.
PKM
The PKM is fed with 150 rounds 7.62mm cartridge in a ammo box. It has similar firepower as the MG3 and the M60 and could be freely switched to "automatic mode" or "3-round burst mode".
Sniper Rifles
Steyr Scout
Renamed to "Schmidt Scout" in game. Has Counter-Strike model but with a scope from Condition Zero.
Heckler & Koch G3SG/1
Named "D3/AU-1" in game. Available for the terrorists faction. While it has a model from Counter-Strike its scope is ripped from Source.
SIG SG550 Sniper
Named "KRIEG 550 commando" in game. Available for the counter-terrorists faction. Has Counter-Strike model, Condition Zero scope.
VSK-94
The VSK94 retain its name in game, Comes with an integrated suppressor, as the new automatic sniper rifle for the counter-terrorists faction. Suitable for use in special operations and use as a SMG.
SVD Dragunov
Named simply "SVD" in game. As the new semi-automatic sniper rifle for the terrorists faction. The user could usually kill a enemy with one shot, although the rifle would became inaccurate when firing the second shot due to the high recoil.
SVD + M203 Grenade launcher
This SVD variant is named "SVDEX" and only available for VIP player in the zombie game mode. It has feature a Barrett style muzzle brake, and a sawn-off M203 and an EOTech Holographic sight.
Accuracy International Arctic Warfare Magnum(AWM)
The AWP is returned from Counter-Strike and named "Magnum Sniper Rifle(AWP)" in game, with a few variations. Model is slightly improved of Counter-Strike and possibly Source scope.
Sako TRG
Named "TRG42" in game. Feed with 10 round mag. Like the AWP, the user could kill an enemy with one shot. But this rifle has different scope. Comes with a variant called the "TRG42 White Gold".
Heckler & Koch SL8-1
Named simply "SL8" in game. Comes with 20 round mag and 25 round for the gold-plated version and high capacity variant. Even though this is the single stack SL8-1 variant, it erroneously uses the shorter double stack magazines of the European/Canadian variants. The high capacity variant feeds from AR-15 magazines, a possible modification for the SL8-1 done by replacing the magazine well and removing part of the receiver. The rifle is not very powerful, but does high rate of fire and has high accuracy.
M24 Sniper Rifle
Called simply "M24" in the game, the rifle is painted with urban camo. Comes with a 10-round mag. The user could usually kill an enemy with one shot in middle range.
Cheyenne Tactical M-200 Intervention
Named as "M400" in game. Feed with 10 round mag. These screenshots show a .338 Lapua model instead of .408 CheyTac model. Like the AWP, the user could kill an enemy with one shot. But this rifle has different scope.
WA 2000
The WA2000 retains its name in game and feed with 12 rounds. It is powerful and accurate although it's available to fire in semi-automatic only. It also comes with a gold-plated variation which fed with 15 rounds.
Barrett M95
The M95 retains its long name in game as "Barrett M95". Suitable to use for destroying enemy helicopters and vehicles. It's also effective for anti-personnel and the user could kill an enemy with one shot.
Remington XM2010 Enhanced Sniper Rifle
The Remington XM2010 Enhanced Sniper Rifle is named the "XM2010", appears as the one of the most powerful sniper rifle in the game and fed with 5 rounds. It is the upgraded version of the M24. It does higher damage but has lower capacity.
Accuracy International AS50
The AS-50 is a anti-material sniper rifle which can fire in semi-automatic and feed with 5 rounds magazine. Like the M95, the rifle is suitable to use for destroy enemy's helicopters and vehicles. It's also effect for anti-personnel or anti-zombies. When it's used for anti-personnel, the user could kill an enemy with one shot.
Blaser R93 Tactical
Named simply as "R93" in game. Currently appear as a skin for the AWM. Still available only in Korean version of CSO.
Accuracy International AW50F
Named "AW50" in game. Currently appear as a skin for the AWM. Still available only in Korean version of CSO.
Others
Crossbow
The crossbow appear as the only "missile weapon" in the game. It fed with 50 rounds arrows and has high knock-back power, effect for engage zombies.
Grenades
M67 Hand Grenade
Named "Fragmentation grenade" in game as the primary weapon for the player in the "Grenade Warfare" mode, it also has a flame grenade variant which available in the zombie modes.
Model 24 Stielhandgranate
Named simply as "M24 Grenade" in game.
Launchers
M79 grenade launcher (Sawn-Off)
Named "M79 Saw-Off" in game. It's frequently used by players in Zombie Scenario Mode due to the weapon could kill at least a dozen of zombies.
M203 Grenade Launcher (Sawn-Off)
Appear as a part of the "SVDEX". The user could blow off enemies with it.
M136 AT4
Named "AT Lance" in game. Available only in the "Human Scenario" and "Metal Arena" modes. It's usually used by players in Human Scenario Mode to engage enemy vehicles.
AT4-CS
The AT4-CS is available in all game modes.
Land Mines
The M14 landmine appears in the zombie union mode.
Unknown Gatling Guns
The RAH-66 Comanche, V-22 Osprey, and UCAV in game are equipped with 30mm Gatling guns.