Descent

Descent was a planned SP mission in Call of Duty 4: Modern Warfare. Very little is known about this level. All that proves its existence is a file called "descent.str" that came with the game's mod tools. The string file includes information about the level, such as its location, the level name, the date, and various objectives.

Plot
From the level's planned string file, the mission would take place in Riyadh, Saudi Arabia. The player's team would be U.S. Marines. The INFO string identifies the Marines as "entering [an] underground command bunker". The mission would take place late in the game, as the date is "Day 6 - 1310 hrs".

Hint strings include the following:
 * Pull [{+usereload}] to pull out your camera.
 * Pull [{+usereload}] to zoom in. \nPull [{+attack}] to take a picture.
 * Hold &&1 to plant the detpack.
 * Jump towards the cable to fast rope down.

The former strings mention the use of a camera. The reload button would zoom in on the target, and the shoot button would take a picture. Aside from those bits of information, it is unknown how the camera would work.

Objectives include the following:
 * Eliminate the Axis naval artillery crews at the docks.
 * Photograph and identify the remains of Al-Assad.
 * Photograph the officer's face on the desk.
 * Photograph the officer's face in the bathroom.
 * Photograph the officer's face under the rubble.
 * Photograph the officer's face by the rubble.
 * Photograph the officer's face by the jail cell.
 * Photograph the officer's face by the broken wall.
 * Plant a detpack on the compromised wall.
 * Secure the Landing Zone.

Note the second objective - "Photograph and identify the remains of Al-Assad." This string means the whole plot for Call of Duty 4 was very different in the beginning. Al-Asad is spelled differently, and he was apparently not killed by a nuclear blast. There is also a weapon called "colt45_alasad_killer", which is presumably the weapon used to kill Al-Asad.

Camera
Most interesting about this level is the use of a camera to photograph the remains of dead officers. After extensive searching, remnants of a weapon called "camera" are in the game. The weapon is available in 5fov, 10fov, 20fov, 30fov, and 45fov versions. However, the model files for the camera are mission. The only known controls are that the reload button would zoom in, and that the shoot button would take a picture.