Left 4 Dead 2

Left 4 Dead 2 is a cooperative first-person shooter video game. It is the sequel to Valve Corporation's award-winning Left 4 Dead. The game launched on November 17, 2009, for Microsoft Windows and Xbox 360 in the United States and November 20 in Europe; in 2010, Left 4 Dead 2 was made available to the Steam client for Mac OS X. It has been ported to Linux but, as of May 2012, has not been released yet. It builds upon the cooperatively-focused gameplay of the original and uses Valve's proprietary Source engine, the same game engine used in Left 4 Dead. The game made its world premiere at E3 2009 with a trailer during the Microsoft press event.

Like the original, Left 4 Dead 2 is set during the aftermath of an apocalyptic pandemic, and focuses on four survivors fighting against hordes of the infected, who develop severe psychosis and exhibit zombie-like tendencies. The survivors must fight their way through levels, interspersed with safe houses that act as checkpoints, with the goal of reaching a rescue vehicle at the campaign's finale. The gameplay is procedurally altered by an artificial intelligence engine dubbed the "Director" that monitors the players' performance and adjusts the scenario to provide a dynamic challenge. Several new features have been introduced: new types of infected, melee weapons, and a story-arc that connects the game's five campaigns together.

When it was released, it received a combination of positive and negative critical and community reactions. It attracted an unusually high volume of pre-release controversy about the game's graphic content. In response, alterations were made to the cover art and both Australia (due to having no R18+ rating) and Germany refused to rate the unmodified edition. After release however, the game was met with critical acclaim and positive reviews.

Setting
Like its predecessor, Left 4 Dead is set shortly after a worldwide pandemic of an infectious disease that rapidly transforms humans into zombie-like creatures and mutated forms that demonstrate extreme aggression towards non-infected (much like the infected in 28 Days Later). Few humans are immune to the disease, still carrying the infection but showing no symptoms. The Civil Emergency and Defense Agency (CEDA) and the U.S. military create safe zones to attempt to evacuate as many American survivors as possible. Left 4 Dead 2 introduces four new survivors—Nick, Ellis, Coach, and Rochelle, who are immune to the disease and have individual back stories that are provided through character dialogue. Like the first game, the five campaigns in Left 4 Dead 2 are set across a story arc, set in the Southern United States, which starts in Savannah, Georgia, and ends in New Orleans, Louisiana.  The four survivors have to fight their way through the hordes of infected, using safehouses along the way to rest and recuperate in order to reach extraction points.

Story
After climbing to the roof of a hotel in Savannah to be rescued, the survivors find themselves abandoned by rescue helicopters, and make their way to the local mall, after hearing word of a second CEDA evacuation point there. After a brief encounter with a gun store owner, Whitaker (voiced by Dayton Callie)the survivors discover that the mall is overrun and all of the CEDA agents have either been killed or have become infected themselves. The four then use a stock car to bust out of the mall and travel towards New Orleans ("Dead Center"). On their way there, they encounter the original survivors featured in Left 4 Dead at the portside town of Rayford ("The Passing"), who allow them to cross the bridge by first filling up its generator with gasoline. Later, they find the highway completely blocked by wrecked vehicles and are forced to travel through a still-operating but abandoned amusement park, and start a huge fireworks-and-lights show used by the rock band, The Midnight Riders, in order to attract the attention of a helicopter pilot ("Dark Carnival").

After being rescued, they realize their pilot has been infected. Nick is forced to kill him, which causes the helicopter to crash into a bayou ("Swamp Fever"). They find brief shelter in a plantation mansion and make radio contact with a Cajun boat captain named Virgil who can get them to rescue, but he needs additional diesel fuel to make it to New Orleans. Amid a torrential downpour, the survivors go ashore, make their way through an abandoned sugar mill to a gas station to get fuel supplies, and return to the boat ("Hard Rain"). Virgil takes them to New Orleans where the military appears to be evacuating civilians. The group head to the extraction point, but discover that the military is actually leaving the city before the bridge is destroyed by an air strike. Judging from their dialogue, the military pilots suspect that the survivors are "carriers" ("The Parish"). Although the survivors' fate after evacuation is left unexplained after the bridge finale, Chet Faliszek, the game's writer, said that the military is taking survivors to cruise ships in an attempt to escape the worldwide infection.

The Sacrifice campaign takes place before the main events of Left 4 Dead 2, sometime before the events of The Passing. The survivors from the Left 4 Dead arrive at the portside town of Rayford in order to search for a boat that could take them to the Florida Keys. After finding an adequate vessel, the survivors manually have to start up generators in order to lift a bridge for their boat to pass through. One survivor (canonically Bill) sacrifices himself in order to kick-start a generator once the lift jams, so that the others may reach safety. This is the end of Bill's story in the Left 4 Dead video game series.

Gameplay
Like its predecessor, Left 4 Dead 2 is a first-person shooter with a heavy emphasis on cooperative gameplay. The game presents five new campaigns, each composed of three to five smaller maps. In the first two to four maps of any campaign, the survivors attempt to reach a safehouse, while the final stage requires the survivors to call for rescue and either survive a prolonged onslaught until rescue arrives, pass through an especially challenging gauntlet of infected to reach a rescue vehicle, or (in Dead Center) collect and deploy fuel cans to facilitate an escape.

Each survivor can carry one main weapon, and either a melee weapon or pistols as a secondary weapon. Though melee weapons cause extra damage to the infected when struck, the survivors can use any other weapon or item for weaker melee attacks and to temporarily push the infected back. Players also carry a flashlight which has infinite battery and makes it possible to see in the dark, but also causes infected to notice the survivors much faster. They may also carry a single first aid kit, special ammo pack, or a defibrillator; in addition to either pain pills or adrenaline shot. They may also carry a single throwable weapon—Molotov cocktails to set an area on fire, pipe bombs to attract any nearby infected to the flashing light and sound it makes until it explodes, and Boomer bile, which can be thrown at infected to cause them to turn on each other.

Because many of the special infected can quickly finish off a survivor if they are not rescued, the game encourages players to stay and work together to traverse the level safely. To enable situational awareness of other players, players are shown the health and status of their fellow survivors. If a player does not have direct sight of another survivor, they will be shown the survivor's highlighted silhouette. As they take more damage from the infected, players move slower. If a survivor's health drops to zero, they become incapacitated and can only fight off the infected using pistols—even if they are carrying a melee weapon—until rescued by another survivor. If a character dies, they remain dead until the next level, unless revived by a defibrillator, or, in Campaign or Single-player mode, reappear in a "rescue closet" to be freed by the other survivors. Should all the survivors be killed or incapacitated, or if all the human-controlled survivors die, the game is over, and players must restart that chapter.

Left 4 Dead 2 retains the three game modes of the original game—Campaign, Versus, and Survival—and adds a new game mode called Scavenge. In Campaign mode up to four human players fight against the computer-controlled infected to make their way between safe houses; any survivor not controlled by a human player is controlled by the computer. In Versus mode up to four other human players take control of the various Special Infected who try to prevent the Survivors from reaching the next safe house. Special Infected are randomly assigned and one player typically controls a "non-pinning" infected which cannot "trap" a survivor (such as a Boomer or Spitter). Occasionally, as determined by the "AI Director", players will become the Tank, who has a massive amount of health and strength. The two teams swap sides once per chapter and are scored based on their play through as Survivors. Points are given during chapter progress, the more distance, the more points. If both teams make it to the saferoom with all four survivors, a 25 point tie-breaker is awarded to the team that dealt the most combined damage as special infected. Versus mode typically requires at least 1 human player on each team. Survival mode is a timed challenge where the survivors are trapped in a section of the campaign maps, and try to survive as long as possible against an unending onslaught of infected. In the new four-on-four Scavenge mode, the survivor players are required to collect and use as many of the sixteen gas canisters scattered about a level to maintain the fuel of power generators, while the infected players attempt to stop them.

The game features a realism mode, which can be enabled at any difficulty for either campaign or versus modes. This mode removes some of the video-game aspects from the gameplay: survivors are not able to see the silhouettes of their teammates; if they die, they can only be revived with a defibrillator kit and will not respawn later in the level. Damage dealt to Infected is also changed, with headshots dealing more damage to enemies, whereas limb or body shots require more shots, making gameplay even more of a challenge. Additionally, the Witch will now kill any survivor it would have merely incapacitated. Items such as defibrillators, throwable items and weapons will only glow when the player is within a few feet, forcing the players to investigate more thoroughly. Designed to force players to work closely together and rely on voice communication, the realism mode was created to give players a way "to be challenged as a team" without having to increase the difficulty level of the game.

Survivor Characters
Left 4 Dead 2 features a new cast of human survivors, which include Coach (voiced by Chad Coleman), a portly high-school football coach with a bad knee (although it does not show in the game); Nick (voiced by Hugh Dillon), an unemotional, sarcastic, and rude gambler and con artist; Rochelle (voiced by Rochelle Aytes), a low-level production assistant reporting on the evacuation for a local television station; and Ellis (voiced by Eric Ladin), a laid-back (and rather talkative) friendly mechanic who will talk about his friend "Keith" and his many adventures with him. We learn that Keith escaped via helicopter.  While the game is intended as a continuation of the original, occurring one week after the first game begins, Valve decided to create a new group of survivors because of the change in location. In addition to the four playable characters, Left 4 Dead 2 also features a supporting character in the form of Virgil (voiced by Randall Newsome), a Cajun boat captain, who appears (voice only) in the game's final two campaigns. This differs from the original game, where NPCs made little more than a single appearance.

Infected Characters
The infected in Left 4 Dead 2 are largely unchanged from Left 4 Dead. While also referred to as zombies, the infected are humans that have contracted a mutated strain of a virus, though neither the source nor nature of this infectious agent are made clear. The most numerous infected encountered by the survivors are the "common infected." Though individually weak, they can swarm and overwhelm the survivors. Damage to the infected In Left 4 Dead 2 is portrayed more realistically, with bullets ripping off bits of flesh and, in some cases, limbs. A new addition to Left 4 Dead 2 is the "uncommon infected" unique to each campaign. By virtue of equipment worn before infection or mutation they possess an ability that separates them from the common infected. In the Parish campaign, for example, the player encounters infected security personnel wearing riot gear, making them almost impervious to gunfire from the front, in the Dark Carnival campaign there are infected clowns who will attract other common infected with the squaking of his nose, while Dead Center features infected civil emergency agents with hazmat suits which are immune to fire.<sup class="reference" id="cite_ref-18">

As in the first game, there are "special" or "boss" infected in addition to the common infected whose mutations grant them special attacks that make them much more dangerous. The presence of such infected nearby is hinted at by sound effects or musical cues unique to each type. The five special infected from the first game return in Left 4 Dead 2, some with modified behavior and skin models. They are: The Boomer, a bloated infected whose vomit and bile (which may be released at will and upon death) blinds the player briefly and attracts a horde of common infected; The Hunter, an agile infected that can pounce on survivors from great distances and screams at the sight of a survivor; The Smoker, an infected that can ensnare survivors with its long tongue from a distance and, upon death, releases a cloud of smoke that obscures vision; The Tank, a gigantic, muscular infected that can punch survivors and toss concrete slabs.; The Witch, a trapper infected who, when provoked by loud sounds, light, or proximity of survivors, will attack her provoker—she is able to incapacitate or kill in one hit.<sup class="reference" id="cite_ref-Left_4_Dead.E2.80.94Infected_19-0"> In Left 4 Dead 2, the Witch now has the ability to wander aimlessly in daylight.<sup class="reference" id="cite_ref-rps_preview_7-3"> <sup class="reference" id="cite_ref-Left_4_Dead.E2.80.94Infected_19-1">

Several new Special Infected are introduced in Left 4 Dead 2, all of which are playable in versus and the new Scavenge game mode.<sup class="reference" id="cite_ref-rps_preview_7-4"> The Charger, an infected with an enormously mutated right arm, can charge into the survivors and seize and separate one survivor from the others whilst pummeling them into the ground, rendering the player helpless until one of their teammates helps them. The Spitter can project balls of stomach acid that splatter across an area, quickly eroding the survivors' health as long as they remain within it; the longer a player loiters, the faster their health drops. The Jockey can jump onto the back of a survivor and steer them into other infected or environmental hazards, whilst clawing at the player's head.

In introducing the new Infected, the development team had to consider how the new abilities would mesh with the existing Infected and any changes they had made to them.<sup class="reference" id="cite_ref-oxmuk_chet_23-0"> One discarded idea for a new Infected included the "Leaker"; the creature, when having taken damage, would shoot out spouts of goo at the survivors, and then would be able to self-detonate like the Boomer. However, this sacrificial act would have given survivors time to escape, and the idea was dropped, though features of the Leaker were built into the Spitter.<sup class="reference" id="cite_ref-oxmuk_chet_23-1">

The Director
As in the first game an artificial intelligence system called the AI Director drives gameplay by procedurally spawning enemies, weapons and items based on the players' performance. In Left 4 Dead 2, the Director has been improved to encourage more participation by players, forcing players through difficult gauntlets to reach the extraction point. It also has the ability to alter elements of the level such as placement of walls, level layout, lighting, and weather conditions, making each play session unique.<sup class="reference" id="cite_ref-rps_preview_7-5"> The Director now rewards players for taking longer or more difficult paths through each episode by providing more useful equipment, such as incendiary or explosive ammo, along these riskier paths.

Development
Development for Left 4 Dead 2 started shortly after the release of the first game—following a short break—building on ideas from the development team to make the next game "bigger and better".<sup class="reference" id="cite_ref-rps_preview_7-6"> <sup class="reference" id="cite_ref-gamasutra_l4d2_leonard_25-0"> The game was given the code name "Carnation" to prevent revealing its details before its official announcement.<sup class="reference" id="cite_ref-arstech_chet_26-0">

Chet Faliszek stated that Left 4 Dead 2 ' s story would explore more of the world of the game, and that Valve had created a full story for the cause and effects of the infection pandemic, including terms that they have used for the AI Director.<sup class="reference" id="cite_ref-arstech_chet_26-1"> Each campaign was purposely designed with a different feel; however, all five campaigns were mapped out at the same time by the entire team to provide the narrative flow and ensure the uniqueness of each campaign.<sup class="reference" id="cite_ref-oxmuk_chet_23-2"> The team used a Left 4 Dead dictionary developed to describe level design and flow within the game to provide a common language for developing the levels.<sup class="reference" id="cite_ref-oxmuk_chet_23-3">

Left 4 Dead 2 contains about 7,800 unique lines of dialog, a 40% increase over Left 4 Dead.<sup class="reference" id="cite_ref-l4d2_shading_27-0"> The writers designed the characters and selected appropriate voice actors who had natural accents for their lines and allowed the actors freedom to help authenticate the roles. They would attend recording sessions for the voice actors and allow them to ad-lib their lines for their characters, often getting new ideas for character dialog to be recorded later, particularly in the case of Ellis (voiced by Eric Ladin) and Nick (Hugh Dillion).<sup class="reference" id="cite_ref-portal_2_writers_28-0"> Randall Newsome, the voice of the boat captain Virgil, was a local actor from Louisiana who naturally spoke Cajun and helped to embellish the role better than the writers could.<sup class="reference" id="cite_ref-portal_2_writers_28-1"> Faliszek wanted to include a "no-nonsense" woman from a Department of Motor Vehicles, but this character did not make the cut.<sup class="reference" id="cite_ref-arstech_chet_26-2"> The developers solicited several bands to include them in the game: Depeche Mode responded eagerly, and allowed Valve to use its music and other imagery in the game, such as on Rochelle's T-shirt.<sup class="reference" id="cite_ref-29">

In development, the programmers wanted to find a way to provide more variation and visual effects for the players, although they were already strained by memory limitations on the Xbox 360 for Left 4 Dead. One key development factor was recognizing a way to create greater variation in the appearance of the common infected through a number of modeling and rendering tasks. Simple changes of the underlying geometry of the model, either the head or the body, with the resulting affects on the texture mapping was one means to create apparent variation. Another means was created by using different head textures along with various blood and dirt maps, and similarly different wounds applied to the body texture. A final means to alter the tone of both the skin and the clothing worn by the infected. As a result, a single infected model could have up to 24,000 variations within the game. This allowed Valve to effectively only keep two to six common infected core models in memory for each level, leaving only the unique infected for each campaign and the special infected as their own unique models. As a result, the memory use for the infected dropped by 50%.<sup class="reference" id="cite_ref-l4d2_shading_27-1"> Valve's programmers also sought how to better represent damage the players did to the infected by showing inflicted wounds in the appropriate location and in a manner based on the weapon used, allowing for the inclusion of more resilient infected creatures in advanced game modes. They had simulated this in Left 4 Dead by having five possible character models that would result from a fatal attack but felt this could be advanced further. Already limited by memory concerns on the Xbox 360 that prevented further variations on the core infected models, the team devised a system of using textures with transparencies combined with ellipsoid culling from any infected character model to simulate the wounds, with several graphical process simplifications to avoid taxing the rendering system. This allowed the team to simulate up to two such wounds on each infected using only 13% of the memory resources of the based system in Left 4 Dead.<sup class="reference" id="cite_ref-30">

Another visual aspect that the Valve team explored was the rendering of water, particularly in the "Swamp Fever" campaign, which takes place mostly in a large swamp area. Valve found early play-testers would become confused with the large, tree-covered map, but by adding hints of water movement in the direction they were to go, there was a significant reduction in players becoming lost on the map. The water maps were created by using the 3D animation tool Houdini against its landscape maps to create realistic water flow patterns as surface maps. These surface maps were then applied in a "flowing" manner instead of the scrolling manner used in previous games. These water effects were further expanded upon for Valve's next game, Portal 2.<sup class="reference" id="cite_ref-31">

Doug Lombardi, vice-president of marketing for Valve, noted that the SDK released for Left 4 Dead would also be compatible with Left 4 Dead 2.

Promotion
PC and Xbox 360 players who pre-ordered Left 4 Dead 2 through participating retailers gained early access to the game's demo, which was released on October 27, 2009 for Xbox Live and October 28, 2009 for PC players, and an exclusive baseball bat melee weapon to be used in game.<sup class="reference" id="cite_ref-33"> <sup class="reference" id="cite_ref-34"> Pre-ordering the PC version of the game through the Steam network also unlocks Bill's beret from Left 4 Dead for use in the PC version of Team Fortress 2.<sup class="reference" id="cite_ref-35"> The demo became available for all PC and Xbox Live Gold users on November 4, 2009 with Xbox Live Silver users gaining access on November 11, 2009.<sup class="reference" id="cite_ref-36"> The demo features the first two maps in "The Parish" campaign.

On October 5, 2009, Valve announced that Left 4 Dead 2 would be promoted by a $25 million advertising campaign, exceeding the $10 million that supported Left 4 Dead. The campaign includes television advertisements during sporting events, on billboards and magazines; and more aggressive advertising for Europe.

Release and Updates
Left 4 Dead 2 was released on Steam on November 17, 2009.<sup class="reference" id="cite_ref-38"> Retail copies were made available some days after, depending on the country.<sup class="reference" id="cite_ref-39">

In March 2010, Valve announced that it would be bringing the Steam content platform to Mac OS X computers; along with it, Steam will be providing native versions of existing Valve games including Left 4 Dead 2 and its predecessor. The games will support cross-platform play, allowing Mac players to play alongside PC players on the same servers, and will also be part of its Steam Play cross-compatible and Steam Cloud titles, allowing a player who has purchased the game on one platform to download and play it on the other platform for free.<sup class="reference" id="cite_ref-40"> The Mac OS X client was released on October 5, 2010.<sup class="reference" id="cite_ref-41">

Shortly after the release, Valve launched a mock website for the Midnight Riders, a fictional rock band referenced and heard in the Dark Carnival campaign.<sup class="reference" id="cite_ref-42"> <sup class="reference" id="cite_ref-43"> This led to speculation that The Midnight Riders could become playable characters in an update, as there are four members in the band, and guitars are featured as weapons in the game. Valve has yet to address these rumors.

Downloadable Content
On December 14, 2009, Valve announced the first DLC installment for Left 4 Dead 2, "The Passing". Though initially planned to be released sometime in March 2010, "The Passing" was released on April 22, 2010. The content costs 560 Microsoft Points for the Xbox 360 and is free for PC and Mac users. The campaign, taking place between the "Dead Center" and "Dark Carnival" campaigns, features the cast of Left 4 Dead 2 meeting with three of the survivors from the original Left 4 Dead. The new group learns that the fourth original survivor, Bill, sacrificed himself to allow his comrades to continue on safely. The title "The Passing" can be interpreted in several ways; to Bill's passing, the brief passing encounter between the two groups, and of the first group of survivors "passing the torch" to the next. "The Passing" contains references to other zombie-themed works, including the games Dead Rising and Plants vs. Zombies, and the movies 28 Days Later, Shaun of the Dead, Dawn of the Dead and its remake. The add-on also features two new weapons, an M60 machine gun which becomes unusable once depleted of ammo, and a golf club for melee.

A prequel to "The Passing", titled "The Sacrifice", was released on October 5, 2010, as an add-on for both Left 4 Dead and Left 4 Dead 2. This prequel ties up the story of the original game, showing the events leading to the meeting of the two groups of survivors in "The Passing" from the point of the Left 4 Dead characters. However, players can choose which character will sacrifice themselves for the others to safely continue on and not just the canonical choice of Bill. Valve also provided the full "No Mercy" campaign from Left 4 Dead as a Left 4 Dead 2 campaign, which is playable with the original Survivors from Left 4 Dead. Though the maps are nearly identical to their appearance in Left 4 Dead, No Mercy in Left 4 Dead 2 contains all of the enhancements of the sequel, including the new Special Infected, Uncommon Infected, melee weapons, additional guns, and the ability to use the new game modes, including Mutations and Scavenge mode.

An additional downloadable content package, called "Cold Stream", will be released July 24 2012 for Xbox 360 and PC.<sup class="reference" id="cite_ref-58"> Valve has announced testing had began on the Xbox 360, and all the original Left 4 Dead 1 maps via L4D Blog. The content is in public beta, available to players for testing and data collection on any issues, with a complete release date on 24th of July.

Mutations
New game modes, Mutations, have been offered every week after "The Passing"'s release; these game modes alter the conditions of play.<sup class="reference" id="cite_ref-shacknews_passing_release_48-1"> <sup class="reference" id="cite_ref-BrightHub_Passing_overview_56-0"> These "Mutations" are only available for a fortnight at a time, though Valve has added the popular "Realism Versus" mutation to the game as a permanent game mode. Other mutations will be available for voting to make encore appearances every four weeks following the popularity of the "Last Gnome on Earth" mutation.

Community Modifaction Support
Similar to Left 4 Dead and other Source Engine-based games, a number of players have constructed new maps, campaigns, and other variations for Left 4 Dead 2, supported by Valve through their software development kit for the game.<sup class="reference" id="cite_ref-58"> With the kit, players have found ways to include the original Left 4 Dead campaigns into Left 4 Dead 2.<sup class="reference" id="cite_ref-59"> Players have also found ways to increase the number of survivors up to 16, duplicating the graphics for the existing survivor characters as needed.<sup class="reference" id="cite_ref-60"> In August 2010, Valve announced that it will promote selected community generated maps, one every two weeks, both by blog posts on their official site, and by offering the map on a number of their dedicated servers.

Reception
Left 4 Dead 2 received strong positive reviews from game journalists, praising the changes made with the new melee weapons and firearms, the new strategies introduced through the new special infected, and the details of the southern locale and individual campaigns compared with the campaigns of the first game. Ars Technica praised the game's replayability and the attention put in every detail.<sup class="reference" id="cite_ref-L4D2review-ArsTechnica_105-0"> Libération also praised the game, commenting that Valve was one of the last game studios making games geared toward hardcore PC gamers.<sup class="reference" id="cite_ref-L4D2review-libe_106-0"> IGN considered that the game improved on the first in every way, and that anyone who liked the concepts introduced by the first game should buy the second.<sup class="reference" id="cite_ref-ign_review_102-1"> Eurogamer also praised the game, and considered that it was "overflowing with personality".<sup class="reference" id="cite_ref-eurogamer_review_98-1"> Left 4 Dead 2 received the Best Xbox 360 Game award at the 2009 Spike Video Game Awards. The game has been nominated for the "Outstanding Achievement in Game Play Engineering", "Outstanding Achievement in Online Game Play", and "Action Game of the Year" Interactive Achievement Award from the Academy of Interactive Arts & Sciences.

Sales
Pre-release sales estimates for Left 4 Dead 2 were positive. As of July 2009, Left 4 Dead 2 ranked fifth in purchase intent out of all upcoming games, with 6 out of 10 polled stating that they would buy the game.<sup class="reference" id="cite_ref-109"> According to Lombardi, pre-orders for the sequel within the month following the announcement were double those for Left 4 Dead at the same time relative to release date.<sup class="reference" id="cite_ref-110"> In a press release on October 5, 2009 Valve announced that, based on the strength of pre-orders, they expect Left 4 Dead 2 to be the fastest selling product in the company's history, with the game's pre-release sales averaging 300% greater than Left 4 Dead.<sup class="reference" id="cite_ref-Valve_Corporation_37-1"> In an interview in November 2009, Chet Faliszek claimed the number of pre-sales of Left 4 Dead 2 were four times that of the original game.<sup class="reference" id="cite_ref-4x_preorder_111-0">

On December 1, 2009, Valve reported that more than two million retailed copies of Left 4 Dead 2 were sold in two weeks, which represents "more than double" the sales of the original game's two week debut.<sup class="reference" id="cite_ref-112"> According to the NPD Group, the Xbox 360 version was the fifth best-selling retail title for consoles in November 2009, with over 744,000 copies sold.<sup class="reference" id="cite_ref-113">

In February 2010, Electronic Arts, Left 4 Dead 2 retail distributor, revealed that the game had sold 2.9 million on retail so far<sup class="reference" id="cite_ref-114"> while Forbes wrote that more than 4 million copies were sold at stores in 2009.<sup class="reference" id="cite_ref-115">

On May 10, 2011, Doug Lombardi mentioned that each of the Left 4 Dead games has sold 3 million copies on the Xbox 360.<sup class="reference" id="cite_ref-116"> On August 11, 2011, in a phone interview with Giant Bomb, Chet Faliszek said that series has sold over 11 million units in total.

Technical Issues
The Xbox 360 version of the game was noted at launch for having serious issues with lag and slowdown in online game modes, the majority coming from using the game's dedicated servers. According to Valve, these problems were due to an unexpectedly huge number of players online on Xbox Live.<sup class="reference" id="cite_ref-autogenerated1_108-0"> It was shortly fixed after release by a server infrastructure change and adding new dedicated servers.<sup class="reference" id="cite_ref-autogenerated1_108-1">

Valve acknowledged problems with the PC version of the game upon launch, including inability to install the game, or users finding it crashes within minutes. Most users reported successful bug fixes from the patches that followed.

Controversy
Left 4 Dead 2 has been a central issue in a number of critical discussions regarding its timing and its graphic and mature content. John Walker of UK-based gaming website Rock, Paper, Shotgun has theorized that this is due to higher expectations for Valve, given the perception of its status as an industry leader.

Boycott
The weekend following the game's announcement at the 2009 E3 Convention, some Left 4 Dead players called for a boycott of Left 4 Dead 2 and formed the Steam community group called "L4D2 Boycott (NO-L4D2)" which grew to over 10,000 members by the end of that weekend,<sup class="reference" id="cite_ref-1up_boycott_63-0"> and reached more than 37,000 about a month later.<sup class="reference" id="cite_ref-tvg_lombardi_64-0"> <sup class="reference" id="cite_ref-65"> In addition to a lack of further Left 4 Dead content, they were concerned with the characters, visuals, and music shown in the E3 demonstration video, feeling these were inappropriate to the first game's aesthetics, and that the release of the sequel so soon after the first game would fracture the community.<sup class="reference" id="cite_ref-1up_boycott_63-1"> <sup class="reference" id="cite_ref-67">

In response to these complaints, Valve marketer Doug Lombardi stated that the announcement of Left 4 Dead 2 at E3 should not be taken to indicate that Valve would no longer support the first game.<sup class="reference" id="cite_ref-tvg_lombardi_64-1"> <sup class="reference" id="cite_ref-68"> He asked the community to "trust [them] a little bit," and told them that while their team was eager to get new material to players of Left 4 Dead, they determined that a sequel would be the best option for several reasons:<sup class="reference" id="cite_ref-valve_protest_reply_32-1"> the demand for new campaigns, enemies and weapons could not be met as a simple DLC;<sup class="reference" id="cite_ref-valve_protest_reply_32-2"> both Faliszek and project lead Tom Leonard found that too much of the content relied on each other, making it very difficult to release incremental patches in the same style as Team Fortress 2;<sup class="reference" id="cite_ref-gamasutra_l4d2_leonard_25-1"> <sup class="reference" id="cite_ref-arstech_chet_26-3"> the development team liked the idea of rolling up the content into a sequel to be released a year after Left 4 Dead ' s release.<sup class="reference" id="cite_ref-gamasutra_l4d2_leonard_25-2"> Faliszek stated that Newell was skeptical of the idea when the team brought the sequel forward, but still allowed the project to go through.<sup class="reference" id="cite_ref-arstech_chet_26-4">

In September 2009, Valve flew two of the boycott group's most prominent members to Valve, in order to playtest Left 4 Dead 2; the two felt that the sequel was well done.<sup class="reference" id="cite_ref-69"> This event, through a series of correspondences made in jest, shortly led to Valve's Gabe Newell and designer Erik Johnson flying to Australia to visit "Joe W-A", a Left 4 Dead modder. Newell jokingly reported that Valve was "boycotting" Joe's new mod for the game when Joe asked when he would be flown to Valve in the same manner as the Left 4 Dead 2 boycotters, but whimsically offered that if Joe was to pay to fly him to the country, he would take a look at it. Joe was able to raise the required funds, $3000, through donations through his website, though ultimately Newell paid for the trip himself, with Joe's collected donations going to the Child's Play charity.<sup class="reference" id="cite_ref-70"> <sup class="reference" id="cite_ref-71">

On October 14, 2009, the initiators of the boycott group announced that they had ended their boycott and were shutting down the 40,000-plus group because Valve was retaining their promise of additional content and fixes for Left 4 Dead, such as the recent release of the "Crash Course" campaign. These gamers also believed that the group itself, losing its purpose, was now being used just to bad-mouth Valve and other players.<sup class="reference" id="cite_ref-72"> In a video interview posted on October 29, 2009, Gabe Newell said, "for people who joined the Boycott Group on Steam ... they're actually pre-ordering the product at a higher rate than Left 4 Dead 1 owners who weren't in the boycott".

Cover Art
Valve was forced to alter its original cover art for the game by the ESRB; the original image depicted the series' iconic hand with its little finger, ring finger and the thumb torn off, which would thus have the index finger and middle finger remaining. It was deemed too explicit, but to appease the ESRB, Valve changed the image so that the fingers were merely bent back instead, but the company was still able to include the torn-off thumb in all regions except for Japan and Germany, where it had to be censored.<sup class="reference" id="cite_ref-coverart_8-1">

The cover was further changed for release in the United Kingdom, as the two-finger sign with the back of the hand faced toward the viewer is considered an insult; the UK cover features the hand facing the opposite direction to avoid this, making it instead the more optimistic gesture for "Victory".

Racism Accusations
Willie Jefferson of the Houston Chronicle, after seeing initial promotional material for the game, considered that several of the infected "appear to be African-Americans" implying a racist approach to the game, and also noted that "setting the game in a city that was a scene of dead, bloated bodies floating by" some years after the impact of Hurricane Katrina was "a bad call".<sup class="reference" id="cite_ref-75"> Faliszek, commenting on Jefferson's claims, considered the supposition to be "utter insanity", and commented that the infected are a mix of all races, and that the game's version of New Orleans is "not a brick-for-brick representation" of the city and were not trying to make any statement about it with the game.<sup class="reference" id="cite_ref-76"> <sup class="reference" id="cite_ref-77"> A writer for Kotaku considered that "Jefferson's seemed to me to be picking a fight where none exists."<sup class="reference" id="cite_ref-78"> Others noted that the appearance of African-American infected simply reflected the racial diversity of New Orleans.

Australian Ban
Left 4 Dead 2 was refused classification in Australia by the Office of Film and Literature Classification (OFLC). It failed to gain a MA15+ rating, the highest possible rating for video games, thus preventing the sale of the game within the country.<sup class="reference" id="cite_ref-ban_9-1"> In its report, the OFLC cited the reason for refusing classification as "The game contains violence that is high in impact and is therefore unsuitable for persons aged under 18 to play."<sup class="reference" id="cite_ref-80"> However, a small number of members of the OFLC board believed the game could merit the MA15+ rating which was used to publish the first Left 4 Dead. It was expected that changes could be made to the game to allow the game to be classified as MA15+ and thus sold in Australia.<sup class="reference" id="cite_ref-81"> Both Lombardi and Newell were "surprised" by the classification refusal.<sup class="reference" id="cite_ref-82"> <sup class="reference" id="cite_ref-au_remake_83-0"> Valve appealed the OFLC's decision about a week after being notified of the ruling, comparing the sequel to its predecessor, which had been classified as MA15+, and the mature ratings the sequel had received from similar rating organizations around the world.<sup class="reference" id="cite_ref-84"> However, as the appeal process, expected to end on October 22, was close to the planned release date, Valve submitted a modified version of the game for classification addressing the concerns the OFLC has stated.<sup class="reference" id="cite_ref-au_remake_83-1"> This version, which no longer contained images of "decapitation, dismemberment, wound detail or piles of dead bodies", was classified as MA15+ by the OFLC, thus allowing for the game's release in Australia, though Valve and Electronic Arts still hoped to have their preferred, unmodified version classified by the OFLC for release.<sup class="reference" id="cite_ref-85"> The appeal of the decision to deny classification to the unedited version of the game was conducted by the independent Classification Review Board, and resulted in the previous ruling to deny classification being sustained. The Classification Review Board cited "insufficient delineation between the depiction of zombie characters and the human figures" as one of the key factors in its classification refusal.<sup class="reference" id="cite_ref-86">

Left 4 Dead 2 ' s classification refusal, as well as for other recent games such as Fallout 3 (has since been rerated MA15+ having the same version as other countries) and Aliens vs. Predator (has since appealed and rerated MA15+ uncut), has reignited debate over the current prohibition of sale and exhibition of video games for mature audiences.<sup class="reference" id="cite_ref-87"> On November 14, 2009, approximately 170 people participated in the "Epic Zombie Lurch" protest in Sydney, Australia, organised by local video gamers in protest of the lack of an R18+ rating for video games in Australia.<sup class="reference" id="cite_ref-88"> In mid-December 2009, the Australian government sought public opinion on the adult classification rating for video games, despite statements by South Australian Attorney General Michael Atkinson believing the issue to only affect a minority of the country's citizens.<sup class="reference" id="cite_ref-89"> Following Atkinson's decision to leave the Attorneys General to be replaced by John Rau, who is reportedly in favour of an R18+ rating,<sup class="reference" id="cite_ref-90"> Valve have revealed that, should the bill be passed, they plan to release an uncensored version of Left 4 Dead 2 for PC in Australia.

German Ban
In order to achieve the highest possible rating given by Germany's Unterhaltungssoftware Selbstkontrolle (Freigegeben ab 18 Jahren gemäß § 14 JuSchG, meaning "Restricted for those below the age of 18"), Valve had to heavily censor the game's violent content similar to the Australian version. However, the international (and thus uncensored) version was indexed by the Federal Department for Media Harmful to Young Persons on December 1, 2009 in order to prevent sellers from advertising or selling it to minors. On February 15, 2010, the Amtsgericht Tiergarten confiscated all European PC versions for violation of § 131 StGB (representation of violence), meaning they may not be sold; however, it is still legal to import (with the risk that the game is confiscated by customs) and own the game. The court said that the game trivializes violence due to its high killing rate and explicit graphical representation of mutilation. They also sensed a strong cynical attitude behind the game's concept.<sup class="reference" id="cite_ref-92"> To make up for the censorship, German players receive exclusive weapons ported from Counter-Strike: Source, which include the Heckler & Koch MP5, Accuracy International AWM, SIG 552, Steyr Scout and a combat knife.

Links

 * 1) "Left 4 Dead 2 Review". GameSpot.
 * 2) "Left 4 Dead 2 GameTrailers Review". GameTrailers.
 * 3) "Left 4 Dead 2 Review". IGN.
 * 4) "Left 4 Dead 2 Review". Official Xbox Magazine.
 * 5) "Valve: Left 4 Dead 2 Sells 2 Million In Two Weeks". Gamasutra.
 * 6) "Valve releases 'L4D2' toolset online". Digital Spy.
 * 7) Left 4 Dead official website