NOTE: All weapons are fictional (except for a couple), but almost all are based off of real world firearms. Also worth noting, all weapons are reloaded correctly and keep track of the +1 in the chamber, rare in games. In fact, every weapon has six different reloading animations (though certain weapons have more or less, depending on how they are operated), due to the Nanosuit's three modes: Armor, Cloak, and Power (or normal).
The following weapons were used in the videogame Crysis 2:
The M12 Nova is a 9mm handgun with a 20 round magazine. The pistol is the same as Crysis' SOCOM pistol, which was based on a mixture of the H&K UCP prototype and Walther P99 with some features from the Heckler & Koch Mark 23 and Heckler & Koch HK45. Interestingly, when the player reloads an empty M12 (or Hammer) in stealth mode, the animation has the player pull back on the slide and release it, instead of using the slide stop.
The Hammer is a handgun that fires (fictional) .50 Compact rounds from a 9 round magazine. The front of the slide and the barrel are based on the Beretta 92FS, the rear of the slide, and the frame, notably the thumb safety, grip safety, trigger, and hammer, are based on M1911-style pistols, the size, the magazine size, and the large caliber round are based on the Desert Eagle. It also features a compensator in front of the slide. Interestingly, when the player reloads an empty Hammer (or M12 Nova) in stealth mode, the animation has the player pull back on the slide and release it, instead of using the slide stop.
The Majestic is a six-shot revolver resembling both the Mateba 2006M and the Mateba MTR-8 firing .50 Compact rounds, the same as the Hammer. Unlike most revolvers, the weapon is reloaded by swapping magazine cylinders rather than simply replacing any spent rounds in the cylinder with fresh ammo. The Majestic also has an M16-style charging handle which is cocked to pull and lock the cylinder into position. In Singleplayer an Assault Scope can be attached.
The AY69 is a 9mm machine pistol with 30 round magazines that fires at 800 rounds-per-minute. It is almost identical to the Heckler & Koch MP7, most noticeable changes are that it has an under-barrel rail instead of a folding vertical grip, much like the MP7A2, and it lacks a sliding stock and flash hider.
A possible Beretta 92FS is seen in the holster of an NYPD officer holding down riots and panic about a quarantine zone in New York, which then causes C.E.L.L., military, and police forces to seal off New York in the wake of the "Manhattan" virus.
The Feline is a bullpup SMG with a 60 round magazine, firing (fictional) 4.7mm Compact rounds at 1200 rounds-per-minute. It looks very similar to the FAMAS Valorisé, with the FÉLIN name in English (the FAMAS FÉLIN being intended for use alongside the Valorisé in reality), crossed with the L22A1, especially the front rail under the barrel. It also resembles the TKB-022PM, or the Korobov, a canceled, bullpup AK prototype.
The K-Volt is an electrostatic pellet gun that fires 6mm electrostatic pellets from a 50 round magazine and functions like an electric airsoft gun, as opposed to a firearm, not needing to be chambered, even on an empty reload. This works because pulling the trigger cycles the "bolt", chambering a round, then firing it, and not cycling after, meaning there is never a round in the chamber. It also has ballistics closer to an airsoft gun than a true firearm. The pellets do minimal kinetic damage but fry the shields on stronger alien units, drain power from nanosuits, and stuns humans making it a situational weapon. It is very similar to a TDI Vector, but with a different type of magazine and a bulkier, FN P90-like front.
Mk.20 Superior Combat Assault Rifle
The SCAR fires (fictional) 4mm Sabot Scar rounds at 700 rounds-per-minute from 40 round magazines. These advanced rifle cartridges are smaller than 5.56mm rounds, but pack almost the same punch, allowing for 40 round magazines with virtually no loss in firepower. As in the Crysis world, it appears as if the weapon won the SOCOM SCAR competition. It heavily resembles a Heckler & Koch XM8 with some elements from the Remington ACR.
Mk.21 Superior Combat Assault Carbine
A compact version of the SCAR, the SCARAB fires at 900 rounds-per-minute, and is seen being used by some members of C.E.L.L. The most noticeable changes are the lack of a carrying handle, a slightly different handguard, and an collapsible stock.
The Grendel is a 6.8mm SPC assault rifle that holds 24 rounds per magazine and fires in 3 rounds bursts. It heavily resembles the Magpul Massoud.
The FY71 from Crysis returns in the Decimation Pack, and holds 30 rounds. It is based on the AK-74M and the Norinco QBZ-03. What distinguishes it from the FY71 in Crysis and its expansion pack is the olive green finish covering a bit more of the gun, a new rail system, a remodeled handguard and magazine, a Magpul CTR stock, and a shorter front sight. The FY71 has higher stopping power with a slightly slower rate of fire and heavier recoil than the one in Crysis.
Colt M4A1 Carbine
On some of the magazine stands there are "Airsoft" magazines, and they have what seem to be an M4A1 Carbine with a few attachments on the cover.
The DSG-1 is a precision rifle firing .405 caliber rounds from a 6 round magazine. As the name implies, it is based on the DSR-1 but with the layout and semi-auto operating system much like that of the PSG-1 or similar HK rifles. It returns from the first Crysis and the changes to the DSG-1 are a shorter stock, a slightly shorter hand-guard and top rail, semi-auto fire mode, and a longer barrel. In the only error in weapon operation in the game, when reloading an empty DSG-1 the player will operate it as if it was an open bolt weapon, which it clearly isn't. After the animation the bolt will remain in the locked back position, however switching away from the rifle and then back puts the bolt back forward where it should be.
The M2014 is an electromagnetic, anti-materiel, gauss sniper rifle, firing 10mm solid slugs from a 4 round magazine. Its overall shape is very similar to a Walther WA 2000.
Underbarrel Gauss Rifle
There is a 2 shot underbarrel gauss rifle that can be attached to the SCAR, similar to the underbarrel grenade launcher and shotgun. Its description is: A miniaturized electromagnetic solid slug projector. As opposed to the other underbarrels, this one uses the weapon's iron sights to aim. Like the others, using this weapon replaces the semi-auto fire mode in the selection menu, since clearly mounting an object under the barrel obstructs the fire selector somehow.
A 12 gauge, 10 shell capacity shotgun based on Crysis XM2014 shotgun, which in turn was based on the Benelli M4 Super 90 though only Crysis: Warheads version was semi-automatic. Through the use of the latest (fictional) 12 gauge rounds it can even be suppressed for covert operations.
There is a lightweight underbarrel shotgun that can be attached to some weapons and has a capacity of 4 rounds. It resembles the Masterkey fitted with a stand-off muzzle device.
Mk.60 Mod 0
The Mk.60 is a medium machine gun firing 7.62mm Armor-Piercing rounds from a 100 round box magazine at 550 rounds-per-minute. It seems to be a future version of the M60.
Heavy Machine Gun
The name of the weapon is actually "Heavy Machine Gun", and it fires the (fictional) .50 HMG round from a 150 round box mag at 400 rounds-per-minute. It can be ripped off its mount and used by the player. The heavy machine gun heavily resembles the experimental XM307 / XM312 Advanced Crew Served Weapon.
GE M134 Minigun
Door-mounted GE M134 Miniguns are seen on Blackhawk helicopters in "The Wall" trailer.
Type 88 GPMG
Launcher - Tactical Armed Grenades
The L-TAG is a lever-action grenade launcher that can hold 5+2 (fictional) 60mm smart grenades of various types. The grenades can be bounced around corners or deployed like a minefield. However, the extra technology in each grenade makes them heavier and more complex, while also limiting the amount of propellant, giving them reduced range compared to other rounds. The grenades also feature an IFF proximity sensor that reduces the likelihood of friendly fire. It is similar in design and function to the M79 grenade launcher, and even has a similar distinctive noise when fired. The L-TAG, unlike the M79, is a bit smaller, features an enlarged trigger guard, and in a bullpup configuration like the Feline.
In earlier press materials the launcher was referred to as Launcher - Tactical Airburst Grenades, but any such functionality seems to have been removed from the final game and the weapon renamed.
Joint Anti-Tank Weapon
The JAW is a single shot disposable rocket launcher that has the option to use limited SACLOS guidance to defeat moving targets and even helicopters at ranges exceeding 500m. Its appearance and function, plus that it can fire only one shot, along with being made by a Swedish company is similar to the M136 AT4.
Underbarrel Grenade Launcher
The underbarreled grenade launcher fires 30mm advanced explosive anti-personnel percussion grenades and is based on the M203.
The Swarmer is a rather bizarre multiple rocket launcher, seemingly very loosely based on the million-RPM Metal Storm demonstrator rig. Each Swarmer is a pre-loaded disposable 64-round launcher with multiple rounds stacked in each of four tubes, and fires rapid 8-round bursts of homing missiles.
Sage Control GL6
In the intro news footage, a C.E.L.L. operative is shown firing a Sage Control GL6 Launcher to suppress riots about the quarantined New York. The same footage is also used in the game Deus Ex: Human Revolution.
X-43 Mk.1 Klystron Emitter
The X-43 MIKE is a battery powered weapon that fires concentrated microwaves which cook the target from the inside out, and can pass through most objects and set flammable ones alight, like plants. It is best described as a "Flamethrower 2.0".
C4 appears as demolition charges that can be remotely detonated.
The M17 fragmentation grenade, which is based on the DM51 hand grenade, are equipped to the player's inventory by default.
The M34 stun grenade, which resembles an M84 stun grenade with different coloring, is seen in the game.
The M18 smoke grenade appears as an additional grenade from the the Decimation DLC pack in an olive green finish.