Dark Carnival

Dark Carnival is the second campaign of Left 4 Dead 2, that takes place at Whispering Oaks carnival. It starts off on a highway with the Survivors heading towards a Ferris wheel in the distance, passing through a motel complex, and eventually reaching the Whispering Oaks carnival. It is the third Left 4 Dead 2 campaign to be announced by Valve.

Trivia

 * This campaign is possibly a reference to the 1997 first person shooter, Blood, in which the fourth level is also named "Dark Carnival" and takes place in a very similar setting.
 * Dark Carnival is similar to the comedy-horror film Zombieland, where the climax takes place in a carnival, and the zombies are alerted by rides being turned on.
 * Dark Carnival is host to a new Uncommon Common Infected, the Clown Infected whose unusual ability is to attract nearby Infected with his squeaky shoes.
 * There also appear to be Infected with T-shirts that read "STAFF", implying they were working at Whispering Oaks when the Infection struck.
 * Dark Carnival's poster is the first poster to feature an infected, as well as the first to be in landscape position, as opposed to every other campaign poster.
 * Coach's and Ellis' clothes have changed in design yet again.
 * The infamous Gnome from Half Life 2: Episode 2 makes an appearance in the poster, just between Ellis' legs. It appears to serve the same purpose, as an achievement and unlocks an avatar reward requires the gnome to be won from one of the mini games in the carnival.
 * The tagline in this campaign obviously refers to the height check carnival operators perform on people to make sure they can ride on certain attractions safely. This tagline may have been influenced by suggestions made on the official forums.
 * One of the safe rooms is located at the beginning of the "Tunnel of Love."
 * In the dialogue before the campaign, it reveals that it was Ellis' idea to go on to the highway, and Coach used to go to Whispering Oaks as a kid.
 * This is the first campaign in which the new laser sights upgrade is seen.
 * This is the campaign used when Valve revealed Scavenge Mode.
 * The car at the start of the campaign is now a race car, rather than a police car, making it obvious that Dead Center's finale will be used in Scavenge mode, due to it being seen as the object the Survivors must fuel in some of the screenshots.
 * Dark Carnival's finale seems to be one of the strangest - it takes place at a big stadium where a famous band was about to have a concert. Survivors have to set off the fireworks and/or say something in the microphone to attract a helicopter.
 * Dark Carnival's music.
 * One of the carnival's mascots, "Mustachio," makes an appearance in a select few mini-games. If the player scores a high enough score, they will unlock an achievement. Additionally, the shooting gallery mini-game unlocks Gnome Chompski, which is the gnome from Half Life 2: Episode 2.