Portal 2

Portal 2 is an upcoming first-person action/puzzle video game, developed by Valve Corporation. It is the sequel to the critically acclaimed 2007 video game Portal and was announced on March 5, 2010. Though initially expected to be released in the last quarter of 2010, it has been pushed back for a 2011 release for Microsoft Windows, Mac OS X, PlayStation 3 and Xbox 360 platforms.

Gameplay
Portal 2 will continue to challenge the player by solving puzzles in test chambers within the Aperture Science Enrichment Center using the portal gun (the Aperture Science Hand-held Portal Device), a device that can create two portals connecting two surfaces across space. Players, as the silent protagonist Chell from Portal, solve puzzles by using these portals to move unconventionally between rooms or to use the ability to fling objects or themselves across a distance. The functionality of the gun has not changed between the games, but within Portal 2, players can take advantage of the bleeding of other physical effects through the portals.[3] Game Informer identified two examples of this: one was the ability to use air currents created by Pneumatic Diversity Vents, a series of transport pneumatic tubes, through a set of portal openings to push a turret over or to draw objects into the suction.[3][6]  The second example was to use the power of Excursion Funnel tractor beams through portals to bring Chell or other objects to otherwise inaccessible areas. The game also introduces special paint-like gels that can be used to impart certain physical effects to a surface such as Propulsion Gel that boosts Chell's speed as she crosses a surface, and Repulsion Gel that allows her to jump from a surface. The player will be required to determine how to transport that gel to appropriate surfaces using portals in order to progress. The gels can also be applied to objects, such as the Weighted Storage Cube crates, that affect their own physical nature. In addition to the Storage Cube, there are new types of portable objects that assist the player, including Redirection Cubes with mirrored, reflective surfaces used to redirect Thermal Discouragement laser beams, Aerial Faith Plates that can launch objects placed on them, and spherical Weighted Storage Balls, which made a brief appearance in the original game in one of the advanced chambers.

While most of the single-player game will take place in the test chambers created by GLaDOS or her personality cores, there will be times where the player will need to move behind-the-scenes in areas beyond the test chambers as they are reconfigured, leaving the player free of GLaDOS's observation and control.

The game will include a two-player co-operative mode in addition to the single player mode. Both players control separate portal guns and can use the other player's portals as necessary; the second player's portals will be of a different color to help distinguish between the two sets. Because of the number of possible portal combinations, the test chambers that the players proceed through are much more difficult than the single-player campaign, encouraging the two players to work together. This includes complicated laser redirection using both series of portals, or working in two separate chambers, performing actions in their side of the chamber to allow the other player to progress in theirs. The game includes voice communication between players for this mode as well as split-screen for players playing locally. Online players will have the ability to temporarily enter a split-screen view to help coordinate actions. Players have the ability to place icons on the game's levels as a means of informing the other player what they need to do.


 * also look at Portal 1 Gameplay

Plot
Portal 2 takes place hundreds of years after the first game. Despite her apparent destruction at the end of Portal, GLaDOS is "still alive". The player controls Chell, the same protagonist from Portal; retroactively patched just prior to the sequel's official announcement, the ending of the first game shows Chell being dragged away by an unseen figure with a robotic voice, where she has been placed in stasis over the years. The game will again take place in the Aperture Science Labs, untouched by human hands but overrun by decay and nature. The player will interact with many of the numerous personality cores (which were seen activating in Portal's conclusion), which have become active and become independent from GLaDOS in the intervening years, using the automated systems of Aperture Science to create their own microcosms within the facility. The cores themselves are unable to move save through overhead rail systems. Chell is awoken by one of these, Wheatley, who has become concerned for the state of decay and seeks to correct it. Wheatley acts as the player's guide during the tutorial and initial stages. Soon, the two encounter the dormant GLaDOS and accidentally wake her; the computer accuses Chell of murdering her years ago. GLaDOS begins to rebuild the ruined facility, and puts Chell under more tests, stating "I think we can put our differences behind us. For science. You monster."

Two new characters will be introduced for the two-player cooperative mode, which will have its own unique plot and setting. These two yet-to-be-named characters include a modified turret gun and a personality core; both units are bipedal and equipped with their own portal guns. Though once part of the networked facility, they have become separate entities and are treated to similar abuse by GLaDOS while Chell is being put through a series of complicated test chambers.

Development
Valve's Doug Lombardi commented that Portal was originally included as an add-on product to The Orange Box as, to Valve, it was a piece of trial software and had considered The Orange Box as a safety net if it failed; Lombardi stated, "There was no way we could have planned for the success of Portal."[3] After receiving high praise and proving its worth, Valve determined that Portal 2 should be its own product, and is committing more resources than it did for the first game for its release. Valve President Gabe Newell has stated that they know what players are looking for in the full sequel, and expect that Portal 2 will be "the best game we’ve ever done." Project manager Eric Johnson commented that the first Portal caught people by surprise and "made them think about games in a different way". Johnson believed their goal with Portal 2 was to find a way to "re-surprise" players, and considered that a "pretty terrifying" prospect. An example test chamber in Portal 2, showing the effect of flora overgrowth and deterioration on the Aperture Science facilities.

Portal 2 was designed to give the player incremental steps in understanding portals and their use within the game. This approach led to two basic types of chambers. The first type, which Valve calls "checklisting", provides a relatively safe environment for the player to experiment with a fundamental aspect of a new gameplay concept. The second type of chamber is one that combines these elements in new ways to make the player think laterally, giving the player a rewarding experience for completing the chamber. Chambers were first developed through whiteboard via isometric drawings, with the developers performing a sanity check on the chamber, before being created into simple levels through the Hammer level editor. Extensive playtesting was used to make sure the solutions to each chamber were neither overtly obvious nor difficult to see, and to observe alternative solutions discovered by playtesters; based on their input, the design team would keep these alternate solutions viable within the level, or would work around and block the alternate solutions if they were too easy. Once a chamber was considered ready to proceed, the Valve artists then would add elements such as detailed texturing, dynamic lighting, and vegetation. These versions would then be sent back for further playtesting to verify the new elements did not prevent players from finding proper solutions, with further iterations between artists and playtesters until such issues were resolved. Johnson stated that Valve's aim was not to make Portal 2 more difficult than the former game, but instead wanted to keep the same idea of a game "where you think your way through particular parts of the level, and feel really smart when you solve it". While the single player campaign in Portal 2 is designed to avoid frustrating the player, the co-operative levels are more focused on coordination and communication, and are recognized by Valve as being much more difficult than the single-player puzzles.

Valve originally had explored using other characters in Portal 2 before returning to the player-protagonist character of Chell from Portal. The artists gave Chell a more utilitarian outfit, something that would have been designed by a computer for identifying and tracking its test subject. Chell was given a hat, envisioned by the artists to help to keep Chell's appearance as a test subject similar to test pilots, as well as adorned with the number 6 to serve as a tracking means for the facilities' computers. They also designed Chell to appear physically capable of completing the test chambers, but with some vulnerability. The two robotic characters created for the co-operative mode were originally based on designs similar to the movie Westworld, looking more human and less robotic. They eventually redesigned the two characters as a modified personality sphere and turret gun, reflecting the character of the Aperture Science facility. This change also took into account the likely numerous deaths players would endure while trying to solve the puzzles together; with human or human-like characters, the deaths would be rather gruesome, but with robotic characters, Valve was able to provide more comical animations as the robots met their fate, such as struggling from being crushed by a lowering ceiling. The artists found the robot design alone related much of the character's background, in part due to the imagery from the previous game, as well as emphasizing the co-operative mode through the robots holding hands.[16] The co-operative gameplay came about from requests from players as well from anecdotes of players working together on the same computer or console to solve the game's puzzles.

Portal 2's gameplay includes a gel mechanic that can alter the physics of surfaces coated with that gel. Valve found that this addition gave players more control over the game world, but as a result, required the chamber designer to be more devious with their solutions to account for the various possibilities of the gel mechanics. The gel mechanic comes from Tag: The Power of Paint, a DigiPen student-developed game that won the 2009 Independent Games Festival Student Competition prize. Tag Team, the group of students that worked on Tag, was hired by Valve. Journalists compared this to the evolution of Narbacular Drop, another DigiPen student project, into the basis of Portal.

Erik Wolpaw will return to write out the game's script in addition to Chet Faliszek, main writer for the Left 4 Dead games, and National Lampoon veteran Jay Pinkerton. The writing team noted that the use of the personality modules allowed them more freedom than in other games for developing these as characters; they would not require facial or body animations, and they could envision the use of more recognizable voice actors for each module. At the 2010 E3 conference, the demonstration version included the voice of Valve animator Richard Lord for the Wheatley personality sphere; Doug Lombardi noted that the audio was simply a placeholder for the demo, but Lord's performance was well-received and made the character as likable as the Weighted Companion Cube from the first game, urging critics to request Valve retain Lord's voice in the final game. GLaDOS will return, introducing each chamber and congratulating the player on completing it; though they could have included intermediate dialog from GLaDOS while the player attempts to solve each chamber, they found this would be distracting to players, and limited her presence in the game to only these points. Wolpaw commented that while many story elements of Portal will be revisited in the sequel, he will likely not return to some of the memes, such as "the cake is a lie", that have been retread over the past few years; Wolpaw stated, "If you thought you were sick of the memes, I was sick of it way ahead of you". The co-operative campaign will include additional dialog from GLaDOS; the original dialog Wolpaw wrote for GLaDOS was aimed to two women, Chell and a new character "Mel", with the assumption of "image issues", but this dialog remains in place even after the change of the co-op characters to robots. After finding that Jonathan Coulton's song "Still Alive", was a large part of Portal's success, Valve will include more music in Portal 2, including further involvement from Coulton. Original Portal designer Kim Swift, however, has left Valve to join Airtight Games.

Portal 2 will be the first Valve product that will simultaneously be released for Windows and Mac OS X computers through the Steam platform. Portal 2 will also be the first game on the PlayStation 3 to support a subset of features from Steamworks, including auto-updates, downloadable content, and community support. When asked about cross-platform play between PC and PS3, Valve developer Erik Johnson said it was "something the team is gunning for." According to developer Mike Dunkle, "The plan is you will be able to play between console and PC." Valve is also not planning on support for PlayStation Move or for 3D television support on the PlayStation 3.

Announcement
Part of the alternate reality game that led up to Portal 2's announcement was the decoding of SSTV images embedded in an update of the original game.

After Portal's release and critical success, Valve employees Doug Lombardi and Kim Swift, indicated that "more Portal" will be coming. Swift suggested the sequel may contain a multiplayer element, but only if this "from a technology standpoint is possible". Previous comments from Swift had suggested that a multiplayer Portal was "less fun than you'd think."[32] On June 10, 2008, Kotaku reported that Valve was seeking voice actors for the character role of Aperture Science CEO Cave Johnson and suggested that the second game may be a prequel to the events in Portal. However, a later update suggested it could be a sequel, with Johnson as another AI.

Four days prior to the game's official announcement on March 5, 2010, a patch was released for Portal. The patch included an additional achievement, "Transmission Received", requiring the player to manipulate the in-game radios in an appropriate manner. This revealed new sound effects that became part of an alternate reality game-style analysis by fans of the game; the effects included Morse code strings that implied the restarting of a computer system, and SSTV images from a grainy Aperture Science video. These images embedded further hints of a BBS phone number that when accessed, provided a large number of ASCII-based images relating to Portal and segments of fictional documents for Aperture Science; many of these ASCII pictures were published art assets for the game as shown in the Game Informer reveal of the title. A second patch two days later altered the game's original ending to suggest Chell's current fate, with additional digital files and resources to further the alternate reality game. These events were seen by gaming journalists to be leading to a forthcoming Portal 2 or other Half-Life game announcement. Following these events, in time with a countdown timer on the BBS, Portal 2 was officially announced. Gabe Newell continues the alternate reality game surrounding Portal 2's announcement during the 2010 Game Developers Conference.

The alternate-reality game continued after the game's announcement. New ASCII images continued to appear on the BBS. At his acceptance speech for the Pioneer Award at the 2010 Game Developers Conference, occurring the week following Portal 2's announcement, Gabe Newell ended his speech presentation with a fake blue screen of death, purporting to be from GLaDOS and hinting at further Portal 2 news at the Electronic Entertainment Expo 2010 (E3). Two weeks prior to Valve's planned presentation at E3, a cryptic e-mail received by game journalists, purportedly sent as a press release from Aperture Science, hinted that the presentation of Portal 2 was canceled but was to be replaced with "a surprise" jointly by Aperture Science and Valve; this has led to some speculation that Half-Life 2: Episode Three may be announced alongside further reveal of Portal 2. In the week prior to E3, Valve reiterated that the "surprise" at E3 would still be about Portal 2, but noted that the game's release has slipped to sometime in 2011, humorously referring to the preservation of "the fabric of Valve Time".

As part of the Sony press conference at E3, it was revealed by Newell that Portal 2 will be available for the PlayStation 3 and will be the only console version to include some features of Steamworks used in the PC and Mac versions, making the game in Gabe's words "the best console version". The news came as a surprise to many journalists, as previously, Newell has made negative comments about the system, calling it "a total disaster on so many levels" Newell jokingly referred to these comments by thanking Sony for "their gracious hospitality and not repeatedly punching me in the face", and said that he was nervous because he was introduced to Sony marketing character Kevin Butler as the "VP of sharpening things".