Survival Mode

Survival mode is a game type on Call of Duty: Modern Warfare: Mobilized and Call of Duty: Modern Warfare 3. On Call of Duty: Modern Warfare: Mobilized, it is exclusive to Single Player.

Call of Duty: Modern Warfare: Mobilized
It is only unlocked if you either use a cheat code, or beat the campaign on Hardened difficulty. Using a cheat code only temporarily unlocks it, while beating Hardened unlocks it permanently.

There are 4 maps in Survival. They are: Withstand, Persistence, Outlast, and Endure. Withstand is in a Bombed-out Apartment Building in Russia. There is debris all around the Apartment for the player to take cover behind. Persistence is in a Military Aircraft Hangar somewhere in South America. There are several large supply cases for the player to take cover. Outlast is in a small Courtyard in South America. Fallen Pillars, Gates, and a Car are all available for the player's cover. Endure, the final map, is in a War-torn Middle-Eastern town. Debris is littered everywhere for cover.

When you first unlock the mode, you will begin with Persistence only. But, when you survive at least 3 minutes, you unlock the next map, and so on. At the beginning of every game, the player starts out with a USP and 3 Frag Grenades, but there are 3 randomly generated weapons that spawn on the ground, and 8 seconds are given for the player to gather these weapons, and to find cover. The weapons found on the ground change every minute. The weapons that can be found are the M4A1 Red Dot, AN-94, AK-74, P90, MP5, MP7, M40A3, AA-12, M249, and the RPG-7. All weapons have a large amount of Spare Ammo, and, in the M249's case, it has a 200-round mag, where it would be found in other modes to have a 100-round mag.

This mode is a bit like Nazi Zombies, as you are in an enclosed space, and fighting for an infinite amount of time, except the enemies are alive, use guns, throw grenades, and never come into the map, as they do not need to. Also, there is no Co-op for this mode.

Call of Duty: Modern Warfare 3
The mode, which comes as part of the new game's updated Spec Ops suite, has players competing against increasingly difficult waves of enemies (in the Horde/Firefight fashion) across Modern Warfare 3's multiplayer maps.