Vector

The Vector is a submachine gun that appears in Call of Duty: Modern Warfare 2, Call of Duty: Black Ops II, Call of Duty: Ghosts, and Call of Duty Online. It was also seen in early trailers of Call of Duty: Modern Warfare 3.

Campaign
The Vector, simply referred to as KRISS within game files, is often found in use by enemies, most notably by the forces of the Ultranationalist Party, more specifically, the Spetsnaz, the Arctic Forces, and Shadow Company. It can be seen with multiple attachments and camouflages throughout the campaign. In "Just Like Old Times", it is Soap's secondary with ACOG Scope and Silencer.

Multiplayer
The Vector has the highest rate of fire and lowest recoil of any submachine gun in the game. The Vector also deals the lowest damage per shot than any other weapon found in the game. The Vector is generally considered to be the one of the easiest submachine guns to use at long range given its low recoil. Despite its submachine gun status, it excels in more open maps, where medium to long range combat is required. The Vector combines the long range accuracy of an assault rifle with the high mobility, rate of fire, and hip fire accuracy of a submachine gun, blurring the line between the two weapon types.

Despite these advantages, the Vector has some flaws. As the Vector burns through ammo due to its high rate of fire, Extended Magazines or the Scavenger Pro perk can be very helpful as this allows the player to continue achieving more kills in a life, or allows the player to kill more enemies before needing to reload. Bear in mind that the Extended Magazines will not increase the player's total ammo but only rounds per magazine. Sleight of Hand is also effective if Scavenger Pro or Extended Magazines are not available, although the reserved ammo will still be used quickly. The Silencer can also be effective since the player would not lose much power even if a silencer is used as it will almost always kill in five shots without Stopping Power, or four shots with it.

In Hardcore, the Vector's high rate of fire makes it a very deadly weapon, since it requires two shots to kill at any distance without Stopping Power, and one shot with Stopping Power at close range in normal circumstances.

Weapon Attachments

 * Rapid Fire
 * Akimbo
 * Red Dot Sight
 * Holographic Sight
 * Silencer
 * ACOG Scope
 * Thermal Scope
 * FMJ
 * Extended Mags

Call of Duty: Modern Warfare 3
The Vector was seen in some early trailers of Call of Duty: Modern Warfare 3. Also, the Vector's textures as well as menu icon can be found in the game files.

Call of Duty: Black Ops II
"Fully automatic submachine gun. Incorporates recoil mitigation technology."

- Description.

The Vector returns in Call of Duty: Black Ops II as the Vector K10. It is very similar to the Vector from Call of Duty: Modern Warfare 2 as it shares the same animations and uses a similar model, the only notable differences are the Vector K10 now holds 36 rounds rather than its original 30 and the foregrip is now missing without the specific attachment, whereas in Call of Duty: Modern Warfare 2 it was attached by default.

Multiplayer
The Vector K10 is unlocked at Level 16, making it the third submachine gun to be unlocked. The Vector K10 is a very balanced submachine gun, potent at close quarters combat but suffering outside of close quarters due to its poor range and damage. Its damage is lower than the PDW-57 or the MSMC, so shot placement is key in order to compensate for its longer time to kill. It is tied with the Chicom CQB for the lowest recoil of any submachine gun with a rate of fire above 937 RPM by default. However if the Rapid Fire attachment is used, the rate of fire is raised to 1420 RPM.

The recoil is relatively manageable and dependably controllable at close ranges. Despite this, the vertical recoil makes landing the required number of shots to kill at longer ranges more difficult, although the high center speed allows the Vector K10 to remain usable when burst fired. Since the Vector K10 already has low damage, equipping a Suppressor has lesser effect on its time to kill than it would on higher damage guns. It does possess the quickest reload-cancel time, although the difference is not significant when compared to others of its class. In conclusion, the Vector K10 has decent stats in almost all categories, but few that topple its peers. It is very comparable to the MP7, only with a lower recoil pattern, slightly less range, and different iron sights. As such, use of this weapon will likely come down to which recoil pattern or iron sights the user prefers.

The Vector K10 gains an unusual benefit from Select Fire, not only does the attachment turn the Vector K10 into a two-round burst submachine gun, but it also boosts the Vector K10's rate of fire to 1250 RPM and lowers the recoil significantly. While this can put a player at a disadvantage at close range due to the need to manually tap the trigger, it also allows the player to eliminate enemies at surprising ranges with greater accuracy and a faster time to kill than normal due to the rate of fire boost that the Vector K10 gains.

Attachments

 * Reflex Sight (unlocked weapon level 2)
 * Laser Sight (unlocked weapon level 3)
 * Suppressor (unlocked weapon level 4)
 * Fast Mag (unlocked weapon level 5)
 * EOTech Sight (unlocked weapon level 6)
 * Foregrip (unlocked weapon level 7)
 * Quickdraw Handle (unlocked weapon level 8)
 * FMJ (unlocked weapon level 9)
 * Long Barrel (unlocked weapon level 10)
 * Target Finder (unlocked weapon level 11)
 * Adjustable Stock (unlocked weapon level 12)
 * Extended Clip (unlocked weapon level 13)
 * Select Fire (unlocked weapon level 14)
 * Rapid Fire (unlocked weapon level 15)
 * Millimeter Scanner (unlocked weapon level 16)

Call of Duty: Ghosts
"Fully automatic. .45 ACP rounds provide highest damage in its class with increased wall penetration."

- Description.

The Vector reappears in Ghosts under the name Vector CRB, although in game files it is referred to simply as KRISS V. It has a black finish rather than the tan finish seen in the previous games, and has a magazine size of 32 rounds. The player starts out with a Vector CRB in "Federation Day" and "Severed Ties".

Multiplayer
The Vector CRB plays similarly to an assault rifle in most cases, as it is much more competitive at medium ranges than most other weapons in its class. It has the longest three-shot kill range of any submachine gun, and is only beat out in long range damage by the MTAR-X, although the Vector CRB has arguably less recoil at long distances. Overall, it behaves very much like the UMP45 from Modern Warfare 3; they have the same rate of fire at 759 RPM, identical magazine sizes at 32, and the increased wall penetration of an assault rifle.

It can be used in a number of roles depending on what attachments and perks are chosen to accompany it. Rapid Fire and Deadeye make the Vector CRB very dangerous in close quarters. Rapid Fire will decrease its time to kill, and its increased damage makes Deadeye very useful in that only one out of two hits needs to deal damage to attain a two shot kill. Alternatively, its longer range and relatively low recoil make it a potent weapon at medium distances where other SMGs might falter. Muzzle Brake can be used to extend this range even further, while an optic at long distances is useful as the iron sights may be obstructive. A Silencer can turn it into a good close-medium range suppression weapon, however, this will severely cut down on the three-shot kill range, which is a coveted stat on the Vector CRB.

The Vector is a versatile weapon that, although not as capable as other SMGs in close range, can compete against assault rifles up to medium and, under the right circumstances, even long range.

The Vector was buffed on the April 3rd patch, along with most other SMGs, to make it a more competitive weapon. It received a 25% increase in its minimum damage range, meaning that its damage will not drop off as quickly as it did pre-patch. This makes it a more viable weapon at medium to longer ranges.

Extinction
The Vector CRB also appears in Extinction, in Point of Contact and Nightfall for $1500. In Point of Contact, it is on the side of the road in the motel area. In Nightfall, it is at the top of the stairs near the communications tower and  leaning against a shipping container in the compound area. It has an acceptable magazine capacity, but not a very high one, being at 30. The only thing about it that may be more useful than the other guns is its faster handling: faster movement speed when aiming down the sights, faster sprint, faster normal movement speed and faster reload speed.

Sights

 * Red Dot Sight
 * ACOG Scope
 * Holographic Sight
 * VMR Sight
 * Thermal Hybrid Scope
 * Tracker Sight

Barrel

 * Flash Suppressor
 * Silencer
 * Muzzle Brake

Under Barrel

 * Foregrip

Mod

 * Extended Mags
 * Armor-Piercing
 * Rapid Fire

Call of Duty Online
The Vector appears in Call of Duty Online.

Call of Duty: Modern Warfare 2

 * The words "Infinity Ward, Encino CA" are etched into the back of the weapon.
 * The orange color in Fall Camouflage for the Vector is slightly darker because the light grey in the texture files is slightly darker.
 * The player's hand model goes through the Vector's magazine housing. While this error cannot be seen normally, it can clearly be seen while reloading and spinning to the left with a high sensitivity.
 * In the Act III misson "Just Like Old Times", the player starts the mission with a Vector sporting a unique black finish instead of the default tan.

Call of Duty: Modern Warfare 3

 * In the DLC mission, Special Delivery, at the start of the mission you can see several construction workers evading to the right, shooting with the Vector. Once killed, the Vector will not drop, but instead disappear.

Call of Duty: Black Ops II

 * On the side of the gun, it is possible to see ".45 ACP" written.
 * On the back side of the magazine, there is an engraving exactly the same as the back of the MPL; the two M's on two sides of a cube. Also, there is writing that says ".45" on the top of the magazine.
 * With the Select Fire Attachment, the Vector K10 fires two bullets in burst mode, instead of the usual three, similar to the AN-94.
 * It is possible for the Vector K10 to fire faster in burst fire mode than in its automatic mode if you hit the fire button fast enough.

Call of Duty: Ghosts

 * Similar to the MTAR-X and the M9A1, it has an unusable flashlight above the barrel.
 * Right behind the flashlight, it says: "SMG .45 ACP."