Resident Evil 6 allows players to select between four scenarios with interwoven storylines. Each scenario follows one of four main protagonists: Leon S. Kennedy, Chris Redfield, Jake Muller and Ada Wong. The player-characters from each scenario will have their own partners whom are controlled by either artificial intelligence (AI) or another player via local or online multiplayer. In addition, each scenario features a different play-style; for example, some player-characters are more vulnerable to attacks whereas others are more resilient. Each central character has unique abilities, which vary from increased reload times and carrying more ammunition. Resident Evil 6 presents new innovations and gameplay mechanics such as rolling in any direction and running whilst shooting and sliding. The game also features a four-player co-operative mode. When playing in single player mode, the player can allow another player to join in online at any time. While performing certain actions, quick time events may occur, in which the player must follow onscreen prompts by pressing buttons or manipulating joysticks within a limited amount of time.
A new feature comes in the form of tablets; players may consume them in order to recover health, and more can be produced by mixing herbs. If one player runs out of health, that player will have a short time to try to defend themselves while their partners attempt to revive them. If any non-AI players are killed, gameplay will resume at the last checkpoint. The game features several primary enemies, including zombies and the newly introduced J'avo. Unlike zombies, J'avo are able to interact with each other to plan an attack, use weapons, and heal themselves. Also some J'avo are susceptible to various mutations that increase their prowess in battle, the type of mutation sometimes depends on location of the injury. There are a total of 15 different mutations within the game. Certain enemies drop skill points when killed, which can be picked up and spent on upgrades such as increased weapon effectiveness or specific ammunition drops. The campaigns feature a "Lone Wolf" ability which allows the player to remove their artificial intelligence companion character. Players can equip three of these upgrades which apply to all campaigns. The game also features a stamina bar; which depletes once the player performs melee attacks, or uses a "quickshot" — which involves shooting a zombie with a headshot instantly. The overall gameplay of Resident Evil 6 is twice as long as its predecessor, Resident Evil 5.
The game features two new modes. "Mercenaries" mode involves players fighting for survival against hordes of enemies. In the PC version, the Mercenaries mode features an exclusive sub-mode named "No Mercy", which involves the cast from Left 4 Dead 2 fighting a total number of 300 enemies against a timer. "Agent Hunt" mode allows players to take control of random enemies in other people's online sessions, however it is only unlocked after the player clears the three main campaigns. The longer the player stays in another online session, the more points they will earn.
On 24 December 2012, Jake Muller, a mercenary of the fictional South-Slavic Edonian Liberation Army and son of late bio-terrorist Albert Wesker, flees from the authorities during a bio-terrorist attack. He partners with Division of Security Operations (DSO) agent and Raccoon City survivor Sherry Birkin, who was sent to Edonia to ensure that Jake escapes safely from the country so his blood can be tested for anti-bodies for the newly developed C-Virus. He agrees to help on the condition of monetary compensation, however, the two find themselves hunted by a hulking bio-weapon known as Ustanak. At the same time, Bio-terrorism Security Assessment Alliance (BSAA) Captain Chris Redfield and his team, including sniper Piers Nivans and demolitions expert Finn Macauley fight against rebels infected with the C-Virus (referred to as "J'avo"). However, they are attacked by the leader of Neo-Umbrella, who refers to herself as Ada Wong and kills most of the BSAA members including Finn by using a device that injects them with the C-virus turning them into monsters, except Chris and Piers. The aftermath causes Chris to go into self-imposed exile, being afflicted with post-traumatic amnesia. Meanwhile, Sherry and Jake's extraction from Edonia by the BSAA is sabotaged, forcing the pair to crash into the mountains, eventually leading to their capture by Ada.
On 29 June 2013, US President Adam Benford has decided to officially reveal the truth behind the 1998 Raccoon City incident and the United States government's dealings with Umbrella, believing that it will curb the current resurgence in bio-terrorist activity. By the President’s side is his friend, DSO agent and Raccoon City survivor Leon S. Kennedy and United States Secret Service agent Helena Harper, but when the venue becomes host to another bio-terrorist attack, Leon is forced to face the infected and mutated President, and kill him. Along the way, the two encounter Ada, and Helena then discloses to Leon that she was blackmailed by National Security Advisor Derek C. Simmons, into aiding the assassination of Benford to save her sister. She also discloses Simmons' affiliation with Neo-Umbrella. Leon and Helena then decide to pursue Simmons into Lanshiang, China while faking their deaths with aid from Ingrid Hunnigan. Meanwhile, Jake and Sherry manage to escape captivity in Lanshiang after being held captive for six months.
At the same time, Chris returns to duty in the BSAA with Piers and a new team, arriving in Lanshiang under the threat of a bio-terrorist attack. Chris recovers from his amnesia and seeks revenge against Ada, resulting in casualties for his squad. Chris and Piers confront Ada, until Leon intervenes. After being informed by Leon, Chris and Piers pursue Ada to an aircraft carrier, destroying cruise missiles laden with the C-virus. Leon, Helena, Sherry, and Jake confront Simmons over his involvement with the outbreaks, where Sherry covertly hands Jake's medical data to Leon in case of their captivity. Leon and Helena corner Simmons, who has been infected by a J'avo, where he confesses to having killed the President to keep him from disclosing the truth behind Raccoon City, which he believes would have led to the US losing its authority. The two temporarily defeat a mutated Simmons while Sherry and Jake are captured once again. While attempting to leave the city, Leon and Helena are warned by Chris that a missile has been launched, however they are too late to stop it. Leon discloses Jake's real identity to Chris and has him rescue Jake and Sherry in a remote oil platform. With the assistance of Ada, Leon and Helena finally kill Simmons.
In the oil platform, Chris and Piers head underground, managing to free Jake and Sherry from captivity before preventing a large-scale attack by a gigantic bioweapon called Haos from the location. Heavily wounded, and in a desperate attempt to save Chris, Piers injects himself with a sample of the C-virus to help turn the tide of the battle, temporarily defeating Haos before evacuating. Aware that the mutation would worsen, Piers sacrifices himself by pushing Chris to an escape pod. After Chris' pod is launched, Haos makes one last attempt to kill Chris but is killed himself by a powerful lightning charge from Piers, which ensures Chris' escape and the destruction of the Neo-Umbrella base. At the same time, Jake and Sherry escape the facility pursued relentlessly by Ustanak, eventually managing to kill him as they ride a rocket-powered lift back to the surface.
In Ada's story, it is revealed that the Ada Wong that interacted with Chris and Piers was actually a doppelgänger created by Simmons, a scientist named Carla Radames, and that the real Ada Wong was aiding Leon and Sherry while destroying the Neo-Umbrella lab in Langshiang. It's soon revealed that Carla is the cause of the game's events, both wanting to get revenge on Simmons for the transformation and take over the world with her bioweapons. Although presumed dead after being shot by one of Simmons' soldiers, Carla attempts a final attack against the real Ada, after having injected herself with a powerful dose of the C-virus, but is killed. After aiding Leon and Helena in their battle with Simmons, Ada reaches the lab where her clone was developed and destroys everything. She then receives a call from someone, accepting a new assignment. With the world saved, the heroes continue with their lives: Leon and Helena are cleared for duty; Chris remains with the BSAA in command of a new squad, overcoming his guilt; and Sherry continues her duty as a DSO agent, while Jake starts a new life fighting zombies in an underdeveloped country with his real identity covered up by the BSAA, with Jake's blood sample able to be used for a C-virus cure.
The game was first conceptualised soon after the release of Resident Evil 5, and began full development in 2010. Resident Evil 5 producer Jun Takeuchi said that he considered a "completely new system" for Resident Evil 6, but later ruled out his involvement with the game. In March 2009, co-producer Masachika Kawata stated that the new instalment was not decided upon, but admitted that it could take Capcom four to eight years to develop. Kawata later claimed that the new game will be drastically different from its predecessors. The game was directed by Eiichiro Sasaki, who also directed the Resident Evil Outbreak series. When development of the game first begun, producer Yoshiaki Hirabayashi wanted to revolve the game around the "ultimate horror entertainment", bearing in mind that the team considered the upcoming Resident Evil 6 to be the flagship title of the horror genre. In a February 2012 interview, Hirabayashi stated that he went to lengths to balance "all of the things people love" about the series, so the team focused to orientate gameplay around horror themes. In March 2012, Capcom admitted that the survival-horror market was too small for Resident Evil, and issued a statement that the development team would instead choose to orientate the gameplay around the action genre.
The development of the game was led by Hiroyuki Kobayashi, who was stated by Capcom to be aiming to "deliver the most impressive Resident Evil title ever both in terms of scope and production values". Capcom also asserted that the game was meant to take an approach to "evolve" the series. The staff wanted to give the game a new setting with Sasaki wishing to place it in China. While the country of Edonia was not modelled from any country in Europe, it was given an Eastern European theme. According to Famitsu, the character of Jake Muller was designed to be "someone today’s young people can empathize with". The game had a development staff of more than 600, making it Capcom's largest production to date. The decision to bring back zombies into Resident Evil 6 was made by Kobayashi, who felt that they were a popular component for the franchise, as well as complying per fans' requests. Hirabayashi admitted that the game had radically changed at the end of the development cycle, due to the new concepts it introduced to the series. On 21 August 2012, Resident Evil 6 went gold and initiated its online service.
An official trailer was released on 19 January 2012. At a Microsoft press briefing at E3 2012, the first gameplay demonstration was shown, depicting Leon and Helena fighting hordes of zombies in China. A playable demo of Resident Evil 6 was scheduled for release on the PlayStation Network and Xbox Live Marketplace on 5 September 2012. Capcom later announced that the demo would become available for both Xbox 360 and PlayStation 3 owners on 18 September 2012. Early access to the demo was included with Dragon's Dogma. As a result of criticism of the first demo, Capcom brought a different version of the demo to the 2012 San Diego Comic-Con, modifying various parts of its gameplay. Originally scheduled to be released on 20 November 2012, the game's release date was pushed forward to 2 October 2012. Prior to the game's launch, several copies of the game were stolen and went on sales in Poland.
Resident Evil 6 was also contained in Biohazard Anniversary Package, a special edition for Resident Evil's seventeenth anniversary, that was released in Japan on 22 March 2013, alongside the release of the PC version. Resident Evil 6 was re-released on PlayStation 4 and Xbox One which included graphical enhancements and all DLC on 29 March 2016.
In response to a public backlash over classifying on-disc content as downloadable content (DLC), Capcom released a patch in December 2012 free of charge. The patch included new camera controls, a new difficulty mode named "No Hope", an option to play Ada's campaign without having to complete the other three, and the addition of an online co-op partner for Ada's campaign simply called "Agent". Unlike any other character in the game, Agent cannot interact with doors and treasure chests; he also disappears when cutscenes are triggered.
On 18 December 2012, a new multiplayer (DLC) was released with three new multiplayer modes: "Predator", "Survivors" and "Onslaught". Predator mode is a series of quick fire rounds with up to six players who take turns as the fearsome Ustanak and have full access to its weapons. The other players in "Predator" mode must avoid capture and being killed by the Ustanak. Human players score points for successful attacks, but also lose points for being caught and/or taken down. This match type is over once all have played as the Ustanak, with the participant with the most points crowned as the winner. Survivors mode is Resident Evil's take on the classic solo and team based deathmatch mode. Survivors is available for 2-6 players. Onslaught is a two player mode where each must clear waves of oncoming enemies. The twist comes when a player completes a combo chain as this will send enemies over to their opponent’s screen.
On 4 April 2013, a Left 4 Dead 2 crossover DLC was released for the PC version, adding the main characters and two monsters from Left 4 Dead 2 to the PC-exclusive The Mercenaries: No Mercy mode in Resident Evil 6. Various weapons, characters, and monsters from Resident Evil 6 have also been added as optionally-downloadable replacement skins on the PC version of Left 4 Dead 2.
The game received mixed reviews upon release. The PlayStation 3 version holds an aggregate score of 74%, PS4 a 60%, XBox One a 63%, PC a 69%, and the Xbox 360 version a 67% as shown on Metacritic,
The game's storyline, themes, graphics, and artificial intelligence were praised by critics. A reviewer from Game Informer stated that despite the game did not "hold back" the decadent experience from being an "unhinged flaming rollercoaster ride". A reviewer from the Official Xbox Magazine concluded stated that the game was an accomplished shooter "on the whole", and a fittingly "thunderous" send-off for Resident Evil, while also praising the length and variety of the game. GameTrailers noted the shift away from the style and tone of past games in the series, yet still praised the overall direction, stating that despite the "old identity stripped away", the game presented itself as a "massive" action game. Richard George of IGN was favourable toward the technical and artistic design of the game, stating that the game was among Capcom’s greatest successes with an "incredibly strong" world, lighting, and creature designs. Ryan McCaffrey of IGN also noted the new enemies as "some of the best" designs and concepts in the history of the franchise. Hollander Cooper of GamesRadar praised the improvements to the controls over its predecessor, stating that the game had an emphasis placed on fluidity and movement, although noted that the cover system "never seems to work right". The Escapist also praised the improved AI companion that "does a decent job of backing you up and taking the fight to the enemy rather than just standing by", however also disliked the cover system, calling it "the most forgettable new feature of the game".
The game's four campaigns received criticism from reviewers. Simon Parkin from Eurogamer was divided over the campaigns, citing Leon's campaign as the strongest and "the closest we get to the series' survival horror roots", along with Ada's as having "diverse flavour". However, Parkin criticised the other two campaigns, stating that Jake's campaign "rarely delights" while citing that Chris' was a "second-rate third-person sprint" with "idiotic" cutscene dialogue. A reviewer from Edge also felt that the campaigns noticeably contrasted in quality more than others. Similarly, Kevin VanOrd from GameSpot concluded that the game's campaigns were the ultimate test of patience for "even the most dedicated", while Destructoid cited Resident Evil 6 as not only a "step back" for the series due to the game's new and unconventional features, but a "step back for commonplace, unassuming action-shooters".
In an interview with the Official PlayStation Blog, Resident Evil 6 executive producer Hiroyuki Kobayashi responded to fan criticism shortly after release, noting the creative differences with fans. He stated "the fans and us as creators are the two parents [...] and just like real parents, you’re not always going to agree on what is best for raising that child," going on to say, "we want to make sure that what we do pleases them but the initial reaction might not always be positive. We do listen to the fans but we can’t be beholden to them at every turn or I don’t think we’ll ever make progress in terms of the series’ development".
While Capcom has dubbed the game as a "dramatic horror", several critics instead noted the game's departure from the survival horror genre compared to previous instalments. Reviewers from GameSpot and GamesRadar noted that the game was no longer considered a survival horror. Destructoid asserted that Capcom had "abandoned any pretense" of the survival horror genre. Many reviewers listed the game's genre simply as a third-person action shooter. After the game's release, Capcom's Masachika Kawata considered the possibility of rebooting the franchise back to its "classic horror roots".
In May 2012, Capcom announced they expected the game to sell 7 million copies by the end of the 2012 fiscal year, however the company lowered their expectations to 6 million due to the game's mixed reception. Upon release, Capcom announced that it had shipped 4.5 million copies worldwide, setting a new record for the company. In October 2012, the game sold 806,000 copies in the United States. According to Capcom, sales weakened following the strong start, with the company admitting that the game would not meet their goals, and consequently lowered their financial projections for the fiscal year as a result. The game had sold 4.9 million copies by April 2013, and, by October the same year, had sold 5.2 million copies worldwide, becoming one of Capcom's best-selling video games.
Despite the slow start and mixed reviews, Resident Evil 6 became Capcom's second best-selling title by 30 September 2015, with a lifetime sales of 6.3 million copies worldwide. In February 2013, Capcom issued in a statement that the game suffered from poor sales due to various development challenges and "inadequate organisational collaboration" across the company. In addition, the PC version of the game sold more than 1 million copies on Steam as of December 2016.