Unit 13 is a game with third-person and first-person elements; movement is carried out in a third-person perspective and combat, first-person and/or third-person view depending on whether or not players elect to use optical attachments. Players can generally select a maximum of two firearms, which are a primary and secondary weapon. The former contains multiple archetypes, such as assault rifles, carbines, shotguns, sniper rifles, machine guns and launchables, while the latter is limited to a pistol; the game automatically issues this and players can never select, swap out or drop their handgun. Enemies may carry different weapons depending on the situation: for example, riflemen would be armed with carbines, pointmen with shotguns, sharpshooters with sniper rifles and high-value-targets with launchers. Interestingly, the opposing faction is never seen carrying a pistol and will always use a primary weapon, regardless of the circumstances.
Most of the game's weapon models seem to be recycled from SOCOM 4: US Navy SEALs, one of the now-defunct Zipper's previous games.
The following weapons appear in the video game Unit 13:
The Bushmaster ACR is the Commando's first and default weapon. Possesses a rather linear recoil pattern and a firing rate that makes it generally useful in a variety of combat circumstances, but it lacks the precision of specialist weapons in terms of effective distance. Can be fitted with a suppressor or muzzle brake and a variable zoom, ACOG or red dot sight.
The AK-47 assault rifle is used by most terrorist infantry personnel and some High Value Targets. Bizarrely, despite carrying 30 rounds per magazine in reality, the game allows one to equip a 40-round magazine (unless, of course, it has an extended magazine by default). It is always fitted with an ACOG no matter the situation when the player picks it up.
Rock SOPMOD M14
The Rock SOPMOD M14 is the Commando's final unlock. It fires in 3-round burst and has an inaccurate 15-round starting magazine capacity instead of 20, but when leveling up the appropriate character it is possible to unlock an extended magazine, increasing the mag size to a more accurate 30 rounds (such magazines do exist for the M14/M1A platform).
Enemies may on occasion use the FN FAL battle rifle. It is a heavy hitting weapon that fires in single-shot or three-round bursts, but in the game it, for some reason whatsoever, is switched to full auto mode, and equips a 20-round 7.62mm NATO magazine. It has a variable zoom sight regardless of the situation, but its blazing fast fire rate significantly limits the potential of this attachment's usefulness.
The FAMAS G2 is the Technician's first unlock. It is unrealistically fitted with a 50-round drum magazine when in fact this would use a 20- or 30-round cartridge (unless, once again, it has an extended magazine by default). It also fires in 3-round bursts which would improve player accuracy at long range but is less effective for spray-and-prey type combat circumstances.
Patriot Ordnance Factory IAR
Seen in the demo but cut from the final game, the POF IAR is used only for one mission "Anu Air Force Base" but nowhere else.
Enemy riflemen may sometimes be seen with the AKS-74U. Because of the reduced size and its rifle-grade rounds, the 74 possesses substantial recoil even at medium-distance combat and should only be counted on as a reliable close-range self-defense weapon.
Heckler and Koch G36C
The Heckler & Koch G36C with a 100-round Beta C-Mag is the Technician's last weapon. Called "AR36".
The Infiltrator's last weapon. Carries 50 rounds per magazine but very little reserve ammo; outclassed by light machine guns in this regard.
Heckler and Koch MP7
The Infiltrator's second weapon. Its blistering fire rate makes it a horrid choice for anything past point-blank firefights.
Heckler and Koch MP5
The Infiltrator's initial weapon. Accurate and reliable at close-quarters, its firing rate chews through enemies in short distances.
Remington 870 Modular Combat Shotgun System
The Remington 870, or R11-87 as it's called in-game, is a single-fire shotgun that somehow possesses a ridiculously high damage and accuracy rating. In reality, slug ammo would be extremely devastating against a target like a deer as compared to a .30-30, taking down even the biggest buck. At close range, buckshot and slugs are great against large animals (and perhaps people, but having no practical use due to legal and ethical reasons). As for why Zipper decided to make such a weapon both a devastating firearm at close distance and a long-range sniper when shotguns in fact suffer from damage falloff at extreme ranges is an absolute mystery.
The Pointman's last unlock and the only fully automatic shotgun in the game. As with the 870, it can fire slug rounds.
Benelli M4 Super 90
Another shotgun which the player can select when assuming the role of the Pointman.
Carried by enemy shotgunners, this weapon fires in a semi-auto mode and is potentially ruinous up close.
Main weapon of enemy snipers. Unrealistically, the SVD's red 'laser-beam' sight gives away its users' positions - a convention made famous by Hollywood movies in general despite the sniper's desire to be stealthy.
The third and last unlock of the marksman on the team. Its accuracy somehow scores only one bar on the rating chart (the highest rating being 10 bars).
FN SCAR SSR
The FN SCAR SSR is seen chambered as a Sniper Support Weapon; the player is able to use this at some point during the game.
Knight's Armament M110 SASS
The M110 SASS is the Marksman's first weapon.
The MK43, fires a heavy 7.62mm NATO round and has the highest maximum capacity of any weapon (800 rounds in total), at the cost of having a sluggish firing rate.
Enemy gunners carry the RPK machine gun. It is generally inaccurate but its blistering firing rate and damage more than compensate for this. The very sound of it firing full auto is also a significant psychological intimidation to most enemies confronting a wielder of this weapon.
Possesses the second highest total magazine capacity of all the game's weapons.
Another GPMG which the player can procure during the game.
A Browning M2HB heavy machine gun is seen mounted on a vehicle in the training course, but the player can never use it.
The M203 40mm grenade launcher can be used by Animal after he achieves level 10. A very strange weapon, it has an M16/ M4-type collapsible butt attached and is generally seen as an assault rifle or carbine's underbarrel attachment, but Zipper Interactive doesn't cotton to such behaviour and forced the player to use it as a standalone weapon.
Unlike its real-life variant, the game's grenade launcher is extremely unfaithful: a round fired too close to oneself automatically kills the wielder. Being hazardous aside, this is highly unrealistic in a realistic combat circumstance for launched grenades would only detonate after traveling a varying distance between 2 and 14 meters based on the specific grenade model used. Not only that, they also have to have revolved a set number of revolutions before their fuses could even prime.
The Rocket Propelled Grenade is seen in the hands of terrorist leaders and High Value Targets, but the player will not be able to procure this and must stick to the M203 (which only Animal can use).
The Five Seven is the one and only handgun that is seen in the game; the player is always armed with it no matter the situation. Strangely, one is able to select a primary weapon and accompanying attachments but the choice for a secondary weapon is missing, and the player will automatically have this pistol equipped with an integral suppressor threaded through the barrel. The character is never able to drop the weapon, swap it for another handgun or otherwise get rid of it.
The training course contains a couple of weapon racks which the player can view but never choose from.
M84 stun grenade
The M84 stun grenade is Animal's choice of grenade. He can unlock it for the entire squad and is the only operative who can gain "double gear", an ability that allows him to carry twice the normal amount of grenades. This applies to the entire squad in general.
M67 fragmentation grenade
The M67 is Python's choice of grenade. He can unlock it for the entire squad.
Composite 4 charges
Chuckles's choice of grenade, even though it's not actually a grenade. He can unlock it for the entire squad.
MK3 A2 concussion grenade
Zeus's choice of grenade. He can unlock it for the entire squad.
The M18A1 Claymore anti-personnel mine is Alabama's choice of grenade, even though it, like the above C4 charges, isn't an actual grenade. He can unlock it for the entire squad.
Ringo's choice of grenade is the M18 smoke grenade. He can unlock it for the entire squad. Using this particular grenade is also the ONLY way to complete stealth operations without killing anybody, which is integral to the non-lethal bonus which contributes to the overall mission score.