Shotgun (attachment)

The Masterkey Shotgun is a weapon attachment in Call of Duty: Modern Warfare 2. It is an under-barrel pump-action shotgun usable with all in-game assault rifles. It is attached in a similar manner to grenade launchers.

In-game
In Multiplayer, it is unlocked for Assault Rifles by getting 20 Kills with the mounted grenade launcher. It is pump-action with a four round magazine, and a capacity of 20 shells. If put onto a weapon with limited close quarters effectiveness like the FAL, FAMAS, ACR, or M16A4, or a weapon that has a small magazine, like the SCAR-H, the custom class becomes more versatile while still allowing for a secondary weapon. This attachment is not often used by players and can allow the user to surprise enemies. It is also faster to switch to this attachment than it is to switch to any secondary weapon other than a handgun. Unlike most secondary shotguns, which fire eight pellets per shot, the Masterkey fires only six pellets, meaning most of them must hit in order to ensure a one shot kill. While moving, the crosshairs grow slightly larger, unlike other shotguns. This shotgun has by far the longest range of all of the shotguns, with its pellets traveling more than double the range of the Model 1887. However, at such ranges it will take multiple shots to kill a target, making it fairly ineffective. The pump speed is slightly faster than the speed of the SPAS-12's, making up for the low damage.

The Masterkey benefits greatly from both Stopping Power and Steady Aim. Steady Aim provides a tighter hip spread, meaning it can focus in more on its target and increase its already enormous range. However, it is not a one hit kill unless in a very short range. Stopping Power gives each pellet an individual damage boost, which allows for a massive overall increase in potential damage if multiple pellets hit.

Many players using the Masterkey damage enemies with their primary weapon and then switch to the shotgun to finish them off when they don't have time to reload. Another common tactic is to equip it while moving indoors and then switch back to the primary weapon while outside.

Many players(not very many) that do use the masterkey shotgun attachment often use it to clear rooms if their primary assault rifle is not good in close quarters (i.e. SCAR-H, M16A4, FAMAS)

It is advisable to use this attachment on hardcore games, especially at HC Search and Destroy.

Trivia

 * When the player switches to the shotgun from the gun it is attached to, they pump it. This would eject a shell if the attachment was chambered.
 * When the player switches to the shotgun from a gun it is not attached to (i.e. a sidearm), they do not pump it.
 * When used along with a Heartbeat Sensor the majority of the Sensor's screen is hidden from the player's field of view (when the shotgun is out), but still beeps.
 * In the Campaign, the Shotgun has a capacity of 7 rounds. In Multiplayer, it holds 4 rounds; this was ostensibly done to preserve game balance.
 * If this attachment is used in conjunction with FMJ via the Bling Perk, both the assault rifle and the Masterkey will be affected by FMJ.
 * The Masterkey and the SPAS-12 are the only pump action shotguns in Modern Warfare 2 multiplayer.
 * The character never pulls the trigger when firing the shotgun.
 * Characters with shotguns attached to bullpup assault rifles would have to hold them in unconventional positions, as standard assault rifles can have their magazines used as makeshift grips.
 * It is possible to "slam-fire" the shotgun. (The pump cycle after each shot does not need to complete before the gun can be fired again. As soon as the pump starts moving forward, it can fire.)
 * The shotgun attachment is the only attachment that will say "with" after the gun name (Ex. ACR w/shotgun).

Video
thumb|left|300px|Video demonstrating the extremely effective range of the shotgun, as well as its low damage