Dead Air

"Get to the runway of Metro Airport for an airlift rescue."

Dead Air is the third campaign in Left 4 Dead. The Survivors must make their way to a runway in hope of catching a plane away from the Infected.

Official description
Guide your team of Survivors out of the downtown core of Newburg's business district, through derelict office floors and still-inhabited cubicles, and out onto the runway of Metro International Airport, where the only thing standing between you and the last plane out of the city is a murderous army of the undead.

Writings on the wall
There are several instances on the rooftops where one may find writing, such as "help need food" or S.O.S. There are also numerous writings about how a bomb will be dropped on the airport. Their predictions seemed to have come true, as the survivors witness the nearly obliterated airport. This is also mentioned in random dialogue by survivors. Near the end of Runway Finale, sometimes the survivors may state the airport was bombed to prevent the Infection from spreading. Also, near the skyway in The Terminal, Francis may say, "What idiot bombed the airport?"

Players may also notice one of the later safe rooms with the writing "WE ARE THE REAL MONSTERS" on the wall, along with various other messages below it telling the writer that they are a moron, telling them that the Infected are the monsters, and somebody even tells them that he wishes that they are dead now. Beneath all of this, written in small letters, is a sentence that states "I miss the internet." Also in one sentence, it claims that the infected were created by the military, and that there is a rumor that the government is giving a cure to the rich, followed by a claim that the virus was made by aliens, along with a writing wondering if this was "first contact".

Several times throughout the campaign, the phrase "God is dead" can be seen. This was a statement originally made by the German philosopher Friedrich Nietzsche, and has heavily been quoted since. Occasionally, the Survivors may respond to the writings, saying things such as, "Oh, no! The zombies killed God!"