Call of Duty: Modern Warfare 2

The player assumes the role of various characters during the single-player campaign, changing perspectives throughout the progression of the story. Each level is a mission that features a series of objectives that are displayed on the heads up display, which marks the direction and distance towards and from such objectives. Damage to the player is shown by blood appearing on the screen. The player's health regenerates as time passes. Tasks vary in their requirements, from having the player arrive at a particular checkpoint, to eliminating all enemies in a specified location, to defending an objective from enemy attack, or planting explosive charges on an enemy installation. The player is accompanied by friendly troops who cannot be issued orders. Laptop computers that contain enemy intelligence appear throughout the campaign and may be collected.