
Some weapons have different stats in multiplayer, such as magazine size, or even completely different abilities. In the former two cases, the player will encounter weapons placed at fixed locations in levels and semi-randomly allocated to enemies, while in the latter two an experience-based system is used to unlock access to new weapons in multiplayer, there is now an additional weapon-based experience system used to unlock upgrades specific to that weapon, including accessories for it. The game is divided into four modes a singleplayer campaign, a series of challenges for up to two players referred to as "Special Ops" mode, a "Survival" mode pitting up to two players against endless waves of increasingly tough enemies, and competitive multiplayer. Modern Warfare 3 uses the standard system of granting the player two "slots" for weapons in the campaign this can be any two weapons, while in multiplayer without the Perk "Overkill" the player is limited to one weapon classed as primary and one classed as secondary.

Call of Duty: Modern Warfare 3 (also known as CoD:MW3 or MW3) is the eighth installment in the Call of Duty series, and the third main entry in the Modern Warfare sub-franchise.
