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Half-Life is a science fiction first-person shooter video game developed by Valve Corporation.In Half-Life, players assume the role of Dr. Gordon Freeman, a theoretical physicist who must fight his way out of a secret underground research facility whose research and experiments into teleportation technology have gone disastrously wrong.
Half-Life requires the player to perform combat tasks and puzzle solving to advance through the game. Unlike its peers at the time, Half-Life used scripted sequences, such as a Bullsquid ramming down a door, to advance major plot points. Half-Life's story is told entirely by means of scripted sequences, keeping the player in control of his or her first-person viewpoint. In line with this, the game has no cut-scenes, and the player rarely loses the ability to control Gordon, who never speaks and is never actually seen in the game; the player sees "through his eyes" for the entire length of the game. Half-Life has no "levels"; it instead divides the game by chapters, whose titles flash on the screen. Progress through the world is continuous, except for breaks for loading.
For the most part the player battles through the game alone, but is occasionally assisted by non-player characters; specifically security guards and scientists who fight alongside the player, assist in reaching new areas and impart relevant plot information. A wide array of enemies populate the game including parasites of Xen such as Head-Crabs, Bullsquids, Head-Crab Zombies and Vortigaunts. The player also faces human opponents, in particular Hazardous Environment Combat Unit (HECU), Marines and black ops assassins who are dispatched to contain the extra-dimensional threats and silence all witnesses.
The original code name for Half-Life was Quiver, after the Arrowhead military base from Stephen King's novella The Mist, an early inspiration for the game. Gabe Newell explained that the name Half-Life was chosen because it was evocative of the theme, not clichéd, and had a corresponding visual symbol: the Greek letter Lambda (lower-case lambda), which represents the decay constant in the half-life equation. According to one of the game's designers, Harry Teasley, Doom was a huge influence on most of the team working on Half-Life. According to Teasley, they wanted Half-Life to "scare you like Doom did". Newell felt that "Half-Life in many ways was a reactionary response to the trivialization of the experience of the first person genre.
The titles of Half-Life and its expansion packs are all named after scientific terms.Half-Life itself is a reference to the half-life of a quantity (such as a radioactive material), the amount of time required for the quantity to decay to half of its initial mass. The Greek letter lambda, which features prominently on the game's packaging and story, represents the related decay constant, as well as the Lambda Complex featured in the game.

Half-Life: Opposing Force is an expansion pack for Valve Software's science fiction first-person shooter video game Half-Life. The game was developed by Gearbox Software and Valve Corporation and published by Sierra Entertainment on November 1, 1999. Opposing Force is the first expansion for Half-Life and was first announced in April 1999. Randy Pitchford, the lead designer on the game, later noted that he believed Gearbox was selected to develop Opposing Force because Valve wanted to concentrate on their future projects. Over the course of development, Gearbox brought in a variety of outside talent from other areas of the video games industry to help bolster various aspects of design. The game was released on Steam on September 28, 2005.
Opposing Force returns to the same setting as Half-Life, but instead portrays the events from the perspective of a U.S. Marine, one of the enemy characters in the original game. The player character, Adrian Shephard, is sent in to neutralize the Black Mesa Research Facility after a scientific mishap causes it to be invaded by aliens, but quickly finds that the Marines are outnumbered and slowly being beaten back by a second alien race and black operations units.
For the most part the player battles through the single-player game alone, but is occasionally assisted by friendly non-player characters. Security guards and scientists will occasionally help the player in reaching new areas and convey relevant plot information. However, Opposing Force also features fellow U.S. Marines who will assist the player in combat to a far greater degree than security guards. Three types of Marines are featured in the game: the soldier will simply provide fire support for the player with a submachine gun, shotgun or machine gun, the combat medic is capable of healing the player and other non-player characters, while the engineer can cut through doors and remove obstacles, allowing the player and their squad to proceed unhindered.
Opposing Force is set in the same location and timeframe as that of Half-Life, taking place at a remote New Mexico laboratory called the Black Mesa Research Facility.
Half-Life: Opposing Force was first announced by developer Gearbox Software on April 15, 1999. The name Opposing Force has a double meaning, referring both to the fact that the player is now one of the enemies in the original game, as well as to Newton's third law of motion.

Half-Life: Blue Shift is an expansion pack for Valve Software's science fiction first-person shooter video game Half-Life. The game was developed by Gearbox Software with Valve Corporation and published by Sierra Entertainment on June 12, 2001. (It was originally set for release in Spring.) Blue Shift is the second expansion for Half-Life, originally intended as part of a Dreamcast version of the original game. Although the Dreamcast port was later cancelled, the PC version continued development and was released as a standalone product. The game was released on Steam on August 24, 2005.
The protagonist in Blue Shift is a security guard, Barney Calhoun, employed by the Black Mesa Research Facility. After a scientific mishap causes Black Mesa to be invaded by aliens, Calhoun must fight his way to safety.
Blue Shift is set in the same location and time frame as that of Half-Life, taking place at a remote New Mexico laboratory called the Black Mesa Research Facility. In Half-Life, the player takes on the role of Gordon Freeman, a scientist involved in an accident that opens an inter-dimensional portal to the borderworld of Xen, allowing the alien creatures of Xen to attack the facility. The player guides Freeman in an attempt to escape the facility and close the portal, ultimately traveling to Xen to do so. As in Opposing Force, Blue Shift shows the events of Half-Life from the perspective of a different protagonist. The player assumes the role of Barney Calhoun, a security guard working near the labs where the accident takes place. Calhoun is responsible for the preservation of equipment and materials and the welfare of research personnel, and after the accident plunges Black Mesa into a warzone, he must work with Dr. Rosenberg, a high-ranking scientist involved in the experiment, to evacuate the facility.
Blue Shift has a double meaning, referring to both the blue shift light phenomenon, and the name of the shift that the protagonist is assigned to.The game was released on Steam on August 29, 2005 along with the High Definition Pack.

Gunman Chronicles is a fantastic total conversion in the genre of futuristic space western first-person shooter developed by Rewolf Software and published by Vivendi Universal on 20 November 2000. To be honest this is the most strange and amazing Half-Life modification that I ever play. The game was originally a Quake deathmatch mod named Gunmanship 101, then it was moved to Quake II's engine before becoming a Half-Life mod. At the Half-Life Mod Expo in 1999, Gunman Chronicles stole the show and Sierra approached Rewolf to make a retail version. Rewolf was given office space, funding and a mapper (Jeff Lane) by Valve Software to help for completing the project. The game was released as a standalone.
The main hero of the game is Major Archer - one of the officers of the elite units of the Armed Forces of the Federation - Gunman. During a reconnaissance operation in the world Banzure Prime, a team was sent to check the cause of loss of communication with the scientific basis of the Federation, which resides on this planet. On the surface of the planet they find the cause of the loss of communication - Xenomes - dangerous apatasaurus-like organisms, rapidly multiplying. The General, seeing his men have no chance by themselves, takes command of one of the Gunmen's dropships and begins performing bombing runs on the attacking Xenomes, destroying several before being captured in the jaws of one of the larger creatures. Meanwhile, the player character, Major Archer, rallies the remaining gunmen and orders them to retreat to the remaining ships and get off-world immediately, assuming that the general is already dead. The General, still alive as his fighter is dragged underground, pleads (apparently unheard) for rescue over the radio, but the Gunmen leave before having a chance to receive the message.
The game skips five years ahead and places the player in direct control of Major Archer, preparing for a mission aboard a Gunman space station dubbed 'Aeronautica'. After a training level, Archer and a small detachment of gunmen are deployed to a dinosaur inhabited jungle planet, under orders to investigate an outdated but extremely high ranking Gunman distress signal. The signal is soon revealed to be a trap, and the gunmen come under heavy attack both from unidentified human forces and the indigenous fauna. The player is eventually forced to fight his way through a series of catacombs, where he encounters the General, still alive despite having been eaten alive on Banzure Prime. He reveals to Archer that the silicon based xenomes are incapable of digesting carbon based humans, and that he, the scientists from the research colony, and the other gunmen consumed by the xenomes managed to fight their way out of the creature's gullets after Archer left them for dead. The vengeful scientists and gunmen have now formed a rogue cell, with the General as its leader, and are engineering new xenome breeds to use as weapons. The General allows Archer to leave, so as to watch him die at the hands of the planet's vicious reptiles, but he manages to sneak onto the Generals cargo ship, bound for a falling moon that plays host to an outdated AI that has been unstable for sometime since the General left it. At the moon, the ship comes under fire from the now fully insane AI's aerial drone. The General dumps the cargo module Archer is hiding in and leaves the AI facility's science team behind.
As Archer progresses through the facility, he learns that the AI's primary battle is not with the humans, but with a major Xenome infestation. Despite the Archer and the AI's best efforts, the Xenomes manage to destroy most of the Kata-Space Anchors that keep the moon from falling to the planet below. The AI and Archer come to a truce, in exchange for help escaping the moon, Archer agrees to take the AI's mainframe core with it. Major Archer and the AI get on an aerial drone, but fail to navigate through an asteroid field and crash land on a desert planet called Icnus which turns out to be the General's main Xenome facility. Archer battles his way through the facility and causes the plant Xenome to break loose.
The AI helps Archer to the General's location and engage in a firefight. The AI Super Drone defeats his Kata-Drone and as he is walking across the balance beam, the plant Xenome comes out of the crevice and eats him once again as he is saying "I will now have to kill you with my bare hands like I did with ...*ate*". More Gunmen troops arrive shortly after and control the Xenome infestation. The AI makes the facility its home.

Half-Life 2, the sequel to Half-Life, is a first-person shooter video game and a signature title in the Half-Life series. It is singleplayer, story-driven, science fiction, and linear.
The game was developed alongside Source and Steam. It introduced the Source game engine and, because of Steam, is the first video game to require online product activation.The game won 39 "Game of the Year" awards, and several publications have named it "Game of the Decade".
The game's original features utilize its detailed physics simulation. Two sections of the game are played by driving vehicles. New environmental puzzles are also introduced through makeshift mechanical systems. Unlike the scripted, button-based puzzles of Half-Life, these revolve around the player's intuitive new ability to pick up, move, and place objects. Solutions involve objects' physical properties, such as shape, weight, and buoyancy. For example, in the first chapter the player is required to stack up crates and barrels, and climb on them to escape through a high window. Part-way through the game, Gordon acquires the gravity gun, which allows him to push large objects and to grab smaller objects from a distance and fling them away at high speeds. These abilities are required to solve some puzzles, and can also be used in combat.
The game does not have cutscenes, and no formal explanation of the story is given. Instead, the player is left to piece together the hints and clues in each chapter. Much of the overarching story that links with Half-Life can be understood through the interactive non-combat scenes with the game's major characters. The facial animation system allows these characters to have realistic expressive interactions with each other.
Half-Life 2 is a work of science fiction which presents a dystopian alternate history of Earth in which the resources of the planet, seemingly including the human species itself are being harvested by an oppressive multidimensional empire, known as the Combine. The game is set around the fictitious City 17, somewhere in Eastern Europe, almost 20 years after the events of Half-Life. During Half-Life, the scientists at the game's Black Mesa Research Facility cause an interdimensional instability, known in the series as a resonance cascade, which Gordon tries to resolve. However, by killing the overlord of the attacking "border-world", Xen, Gordon unwittingly widens the dimensional rift, which leads to disasters on Earth.
Some time after the ending of Half-Life, this instability attracts the attention of the Combine, and they invade. Humanity surrenders at the conclusion of the resulting Seven Hour War. City 17 becomes the home of the gigantic Combine Citadel, and Dr. Wallace Breen, who had managed "the Earth's surrender," is appointed there as Administrator to supervise the survivors on behalf of the Combine. Unable to procreate because of the Combine suppression field, humanity matures, and no children remain. The Combine implements a brutal police state of Civil Protection officers and Overwatch Soldiers, and the underground Lambda Resistance forms.
For Half-Life 2, Valve Corporation developed a new game engine called the Source engine, which handles the game's visual, audio, and artificial intelligence elements. The Source engine comes packaged with a heavily modified version of the Havok physics engine that allows for an extra dimension of interactivity in both single-player and online environments. The engine can be easily upgraded because it is separated in modules. When coupled with Steam, it becomes easy to roll out new features. One such example is High Dynamic range Rendering, which Valve first demonstrated in a free downloadable level called Lost Coast for owners of Half-Life 2. HDR is now part of all Valve games.
Half-Life 2 was originally intended to be a darker game with grittier artwork, where the Combine were more obviously draining the oceans for minerals and replacing the atmosphere with noxious, murky gases. Nova Prospekt was originally intended to be a small Combine rail depot built on an old prison in the wasteland. Eventually, Nova Prospekt grew from a stopping-off point along the way to the destination itself.
The book, Half-Life 2: Raising the Bar, revealed many of the game's original settings and action that were cut down or removed from the game.

Half-Life 2: Episode One is the first in a series of episodes that serve as the sequel for the 2004 first-person shooter video game Half-Life 2. It was developed by Valve Corporationand released on June 1, 2006. Originally called Half-Life 2: Aftermath, the game was later renamed to Episode One after Valve became confident in using an episodic structure for the game. Similar to Half-Life 2, Episode One also uses the Source game engine. The game debuted new lighting and animation technologies, as well as AI sidekick enhancements.
The game's events take place immediately after those in Half-Life 2, in and around war-torn City 17. Episode One follows scientist Gordon Freeman and his companion Alyx Vance as they fight in humanity's continuing struggle against the transhuman race known as the Combine. When the story begins, Gordon wakes up outside the enemy's base of operations, the Citadel, after being left unconscious from the concluding events of Half-Life 2. During the course of the game, Gordon travels with Alyx as they attempt to evacuate the city. As the game comes to an end, Gordon and Alyx are caught in a major accident, and both of their fates are revealed in the sequel, Episode Two.
Valve views episodes One through Three as tantamount to a standalone release. Episode One is available as part of a bundle package known as The Orange Box, which also includes Half-Life 2, Episode Two, Team Fortress 2, and Portal. Episode One received a generally positive critical reaction, and the co-operative aspects of the gameplay received particular praise. A common criticism of the game was its short length, leading several reviewers to say that the game's four to six hours of gameplay do not justify its price.
In Episode One, a first-person shooter video game, players make their way through a linear series of levels and encounter various enemies and allies. The gameplay is broken up between combat-oriented challenges and physics-based puzzles. Episode One also integrates tutorial-like tasks into the story to familiarize the player with new gameplay mechanics without breaking immersion. A heads-up display appears on the screen to display the character's health, energy, and ammunition. Throughout the course of the game, the player accesses new weapons and ammunition that are used to defend the character from enemy forces. Unlike in Half-Life 2, where Gordon's initial weapon is the crowbar, the player first acquires the gravity gun, which plays a crucial role and allows the player to use physics to manipulate objects at a distance in both combat and puzzle-solving scenarios.
The artificial intelligence (AI) for Alyx Vance, Gordon's companion, was designed specifically for co-operative play in Episode One to complement the player's abilities. The developers described Alyx's programming for Episode One as a "personality code" as opposed to an "AI code", emphasizing the attention they gave to make Alyx a unique and believable companion. For part of the code, she was specifically programmed to avoid performing too many mechanical or repetitive actions, such as repeating lines of dialogue or performing certain routines in combat situations. Examples of this co-operative gameplay include combat in underground levels. In this scenario, the player can conserve their ammunition by using a flashlight to help Alyx spot and kill oncoming enemies. Similarly, Alyx will often take up strategic positions and provide covering fire to keep the player safe while they travel to a certain area or perform certain actions.
Half-Life 2: Episode One is the first in a trilogy of episodes serving as the sequel of the 2004 first-person shooter video game Half-Life 2. Valve explained that the focus of Episode One was character development, in particular that of Gordon's female sidekick and friend Alyx, because she accompanies the player for virtually the entire game. Episode One deals with the events and issues set in motion during Half-Life 2. You've done critical damage to the Citadel. The whole place is going to go up, taking out City 17 and what's in its immediate radius. You and Alyx are leading the flight from the city getting up close and personal with some of the creatures and sights from the end of the game. Because of Alyx's significant involvement in the game, Valve made modifications to her AI that allowed her to react to the player's actions. Modifications include commentating on objects the player manipulates or obstacles they have overcome. She also acts as an important device in both plot exposition and directing the player's journey, often vocalizing what the player is required to do next to progress. The game runs on an upgraded version of Valve's proprietary Source engine, and features both the engine's advanced lighting effects, and a new version of its facial animation/expression technology. Upgrades to enemy AI allow Combine soldiers to utilize tactics previously unavailable to them. For example, Combine soldiers were given the ability to crouch while being fired upon in order to duck underneath the player's line of fire. While no new locales were introduced in Episode One, large alterations were made to the appearance of both City 17 where the game takes place and the Citadel from the end of Half-Life 2 to reflect the changing shape of the world and remind the player that their actions have major effects on the story line. The Citadel has degenerated from the cold, alien, and imposing fortress of the previous game into an extremely unstable state. This provides a visual cue to the player of the catastrophic damage they inflicted, and it allows for the introduction of new gameplay elements that accentuate the dangers which come with the Citadel's imminent collapse. In addition, it serves a thematic purpose by highlighting the weakening of the Combine's dominance in City 17. Likewise, City 17as been altered to reflect the aftermath of the resistance's open rebellion, with vast swathes of destroyed buildings, and the introduction of foes previously kept outside its confines in Half-Life 2 to emphasize the scale of the uprising. Episode One earned a scores of 87% and 86% on review aggregators Metacritic and Game Rankings respectively. IGN awarded Episode One with the title of "Best PC FPS of 2006" and described it as a "great bang for the buck using Valve's new episodic plan", although it did not offer "the complete experience that Half-Life 2 was".

Half-Life 2: Episode Two is the second episode in a series of sequels to the 2004 first-person shooter video game Half-Life 2. It was developed by Valve Corporation in tandem with Episode One, the first game in the series, and released in Q4 2007 via Valve's Steam content distribution platform.The episode was released both separately and as a part of a bundled package, The Orange Box.
Episode Two gameplay consists of expansive environments, travel and reduced linear play, continuing Valve's policy of orienting each episode around a particular theme or set of technologies. Following the closing events of Episode One, it sees Gordon Freeman and the series' other major characters moving away from City 17 to the surrounding countryside. As with the its predecessors, the game is played in the first person as series protagonist Gordon Freeman against transhuman troops, known as the Combine, and other hostile alien creatures. Levels are linear, consisting of puzzles and first-person shooter game-play. Sequences involving vehicles are interspersed throughout the game, breaking up moments of combat.
One of the focal points of Episode Two was meant to be increased use of vehicles in open areas. However, the game retains its original linear style until the final battle. Episode Two has more puzzles than Episode One, including the biggest physical puzzle yet in the series-a damaged seesawing bridge. The game features numerous "achievements" (similar to Playstation 3's Trophies and Xbox Live's Achievements) for carrying out certain tasks. Some are essential to game progress, such as helping fight off an antlion invasion, or defeating the first Hunters. Others are optional tricks or feats the player can perform, such as killing a Combine soldier with their own grenade or running down a certain number of enemies with the car. Episode Two featured a new Hunter synth, which had just been seen briefly in a recorded message in Episode One. The Hunter serves as one of the most dangerous enemies within the game and as means of emotional development for Alyx Vance. The Hunter is a powerful and resilient enemy which players must often run from while seeking a means to fight back; Episode Two's environments are designed with this in mind. Hunters primarily attack the player by bracing themselves and firing bursts from their flechette cannon. Four flechettes can vaporize an ordinary human soldier. If they do not strike a living target, the flechette charge up for several seconds and then explode, dealing minor damage to everything nearby. Hunters may also conduct a charging attack or strike with their legs if the player gets too close. Hunters are vulnerable to all weapons, but to compensate, are still quite resilient, making explosives and the pulse rifle's charged energy ball the most attractive options. Objects thrown with the gravity gun are also effective, especially if the player catches some of their flechettes with the object before hurling it (one of the in-game Achievements). In outdoor environments, they can be run over with a vehicle. Two new forms of Antlion apear in the game. The first is the Glow-in-the-Dark Antlion Grub, a harmless, worm-like creature which functions as a minor health pickup and a light source. The second is the Worker Antlion (or 'acidlion') whose body produces a powerful and poisonous acid. In addition to a ranged acid spit attack, they also explode when killed, launching acid around them in a short radius, making them dangerous close-combat opponents. Although they are thematically similar to the bullsquids of the original Half-Life, they are functionally closer to the poison headcrab- as an enemy that the player will instinctively prioritize as a target. A new antlion guardian, which has glow-in-the-dark features, was also added. This "Guardian" hunts and attacks Gordon Freeman as the player endeavors to take the larval extract the Guardian protects. The vortigaunt that accompanies the player forbids him from harming the guardian, fearing the extract will be ruined if he does. The player must therefore accomplish his goal while being harried by a creature he cannot eliminate, though the player is eventually given the chance to kill it. Episode Two features no new additions to Gordon Freeman's inventory, but introduces a new form of Gravity Gun 'ammunition', the 'Magnusson Device', named after the egotistical head of the White Forest base rocket project, Dr. Magnusson. Prior to the game's release, this weapon had been referred to as the 'Strider Buster'. The item is useless on its own-it must be deployed via the gravity gun. Large sections of the game feature a car which resembles a gutted-and-rebuilt 1969 Dodge Charger. It appears to have been tuned for performance. A radar system is installed later in the game, allowing the player to locate Rebel supply caches. In the final battle, a rear-mounted storage rack for Magnusson Devices is added and the radar is adjusted to track enemies and Magnusson Device dispensers. A homing unit is also installed so the player can quickly locate the car in the chaos of the final battle via a readout in the Hazardous Environment suit.
In contrast to Episode One's entirely urban setting, Episode Two sets the action in rural areas, villages, forests, as well as mining facilities and mountain caves. The exact location remains vague, with signs in Russian still hinting at a generic Eastern European setting, although gas pumps with the prices displayed in Swedish have added to the confusion. The gameplay is in parts, and, to an extent less geographically linear than in the previous games, with the climactic fight in particular taking place across an entire map rather than in an enclosed arena.
The game had an average score of 90% based on 21 reviews on the review aggregator Game Rankings. On Metacritic, the game had an average score of 90 out of 100, based on 18 reviews.
Dan Adams of IGN rated the game 9.4 out of 10 and praised its improved visuals and expansive environments, but cited the short six-hour length as a drawback.

Counter-Strike (shortened sometimes to CS) is a tactical first-person shooter video game developed by Valve Corporation which originated from a Half-Life modification by Minh "Gooseman" Le and Jess "Cliffe" Cliffe. The game has been expanded into a series since its original release, which currently includes Counter-Strike: Condition Zero, Counter-Strike: Source, and Counter-Strike: Global Offensive. Counter-Strike pits a team of counter-terrorists against a team of terrorists in a series of rounds. Each round is won by either completing the mission objective or eliminating the opposing force.
Counter-Strike is a first-person shooter in which players join either the terrorist team, the counter-terrorist team, or becomes a spectator. Each team attempts to complete their mission objective and/or eliminate the opposing team. Each round starts with the two teams spawning simultaneously.
A player can choose to play as one of four different default character models (four for each side, although Counter-Strike: Condition Zero added two extra models, bringing the total to ten). Players are generally given a few seconds before the round begins (known as "freeze time") to prepare and buy equipment, during which they cannot attack or move. (one notable exception is that a player may receive damage during freeze time. This happens when a map is changed to spawn players at a certain height above the ground, thus causing fall damage to the player. This is a method map designers use to alter the starting "HP" of players on a map). They can return to the buy area within a set amount of time to buy more equipment (some custom maps included neutral "buy zones" that could be used by both teams). Once the round has ended, surviving players retain their equipment for use in the next round; players who were killed begin the next round with the basic default starting equipment.
Standard monetary bonuses are awarded for winning a round, losing a round, killing an enemy, being the first to instruct a hostage to follow, rescuing a hostage or planting (Terrorist)/defusing (Counter Terrorist) the bomb.
On March 24, 1999, Planet Half-Life opened its Counter-Strike section. Within two weeks, the site had received 10,000 hits. On June 19, 1999, the first public beta of Counter-Strike was released, followed by numerous further "beta" releases. On April 12, 2000, Valve announced that the Counter-Strike developers and Valve had teamed up.

Counter-Strike: Condition Zero

Counter-Strike: Condition Zero (CS:CZ) is a single/multiplayer video game and the follow-up to Counter-Strike. The game was released in 2004 using the GoldSrc Half-Life engine. CS:CZ features a multiplayer mode, which features updated character models, textures, maps and other graphical tweaks. Unlike other Counter-Strike games, Condition Zero also contains a single-player mission pack with the player playing as counter-terrorist alongside bots. The player unlocks maps and more effective bot teammates as he or she passes certain requirements for each map while playing as a counter terrorist. These requirements include targets such as "kill 3 enemies with a Bullpup" or "win a round in 60 seconds". Counter-Strike bots are a prominent part of Condition Zero gameplay.
With its extensive Tour of Duty campaign, a near-limitless number of skirmish modes, updates and new content for Counter-Strike's award-winning multiplayer game play, plus over 12 bonus single player missions, Counter-Strike: Condition Zero is a tremendous offering of single and multiplayer content.
Condition Zero started development in 2000 by Rogue Entertainment, initially announced in May 2001 at E3 of that year. Rogue's producer for the game, Jim Molinet, later that year moved to Sony and the development company went defunct, leaving Valve with the development. Later, they gave it to Gearbox Software, the developers of the Half-Life expansion packs, so that Valve could focus on the development rival Team Fortress 2 and its new engine.
After a few developmental delays, it missed its late 2002 deadline and was given over to Ritual Entertainment, who completely remade the game into a single-player one with 20 unconnected missions. They enhanced the AI of the original Half-Life to create the initial bot AI. It was expected to have a release in early 2003 with a secondary multiplayer mode, and developed alongside the Xbox version of Counter-Strike.

Counter-Strike: Condition Zero Deleted Scenes

Condition Zero: Deleted Scenes is what is left over from Ritual Entertainment's dropped share of development, a series of 18 unconnected single-player missions.
Deleted Scenes was originally the focus on the game with standard multiplayer included. However, after declaring the game gold and handing out review copies of Ritual's work, Valve saw an average review score of around 60%. The companies retracted the gold status and work on Condition Zero was essentially begun again. Ritual's share of development was dropped, and Turtle Rock Studios eventually made its own version. The final game contained Ritual's single-player portion, called Deleted Scenes, along with Turtle Rock's version.
Several weapons from the "lost contents" have made an appearance in Deleted Scenes, including the M72 Light Anti-Armor Weapon, and the M60 Machine Gun. Some are limited to the AI terrorists, such as the machete and Rogue Entertainment's controversial suicide belt. Some reconnaissance weapons including the blow torch, radio, fiber-optic camera and remote control bombs. Players can also carry up to three grenades instead of the usual one. Moreover, the power of players' Kevlar Armor is boosted, better protecting players from many projectiles and bullets.
Some weapons were completely reanimated. This includes the Colt M4A1, FAMAS and Galil with the exception of the SIG SG 552 which uses its "beta animations". Weapon textures are also slightly modified. The weapons are colored a bit differently from their Counter-Strike counterparts, such as the Arctic Warfare Magnum which is now brown instead of green, the Steyr AUG and the Colt M4 carbine are now two-tone police black instead of the usual colors. It initially came with twelve missions, but later Steam updates added six additional missions that were cut from the initial release. There is a small community for Deleted Scenes, and a few custom maps have been released.

Counter-Strike: Source (officially abbreviated CSS) is an FPS video game developed by Valve Corporation. It is a complete remake of Counter-Strike using the Source game engine. As in the original, Counter-Strike: Source pits a team of counter-terrorists against a team of terrorists in a series of rounds. Each round is won either by completing an objective (such as detonating a bomb or rescuing hostages) or by eliminating all members of the opposing team.
Counter-Strike: Source is a remake of Counter-Strike, and retains its team-based objective-oriented first-person shooter style gameplay. The aim of playing a map is to accomplish a map's objective: defusing the bomb, rescuing all hostages, or killing the entire opposing team. The ultimate goal of the game is to win more rounds than the opposing team. Once players are killed, they do not respawn until the next round on most servers. This gameplay feature distinguishes Counter-Strike from other first-person shooter games, where players respawn instantly or after a short delay.
Moving and shooting also work differently than they do in other first-person shooters. Shooting while moving dramatically decreases accuracy, and holding the trigger down to continuously shoot produces severe recoil. This can be difficult for beginner players to compensate for because the player's crosshair does not correspond with where the bullets actually hit. Shot damage depends upon where the bullet hits, with hits to the head often being lethal.

Team Fortress Classic, also known as Team Fortress 1.5 or simply TFC, is a team-based multiplayer first-person shooter video game developed by Valve Corporation. It is a remake of the Team Fortress modification for Quake. Team Fortress Classic was originally released for Windows on April 7, 1999 as a free addition to Half-Life. A standalone version was later released with Valve's Steam system in 2003. The development of Team Fortress Classic was led by John Cook and Robin Walker, the designers of the original Team Fortress modification.
The game was originally announced in 1999, powered by Valve's GoldSrc engine. The designers of the Team Fortress modification were contracted by Valve to develop Team Fortress 2, but initially remade their original work on Valve's game engine. The game itself involves a number of teams, each with access to nine classes, competing in a variety of scenarios such as capture the flag, VIP protection and territorial control. In June 2000, the game underwent a significant upgrade, adding new player character models and game modes. As of 2008, the game is one of the ten most played Half-Life modifications in terms of players, according to GameSpy In 2010, the game was included as one of the titles in the book 1001 Video Games You Must Play Before You Die.
Team Fortress Classic revolves around a number of teams competing in a variety of game modes with players selecting one of nine classes to play as. Typically, players have the choice of two equal teams, red and blue, although certain game modes allow for more than two teams with access to different classes. Each game can sustain a maximum of 32 players. The way a player acts in a game is mostly defined by which class they select, and as such, Team Fortress Classic relies heavily on teamwork between players of different classes.
This aspect of teamwork is what makes Team Fortress unique. Before the game was released, most gamers were playing games such as Doom which were in a straight forward death match format. Team Fortress not only offered objective based gameplay in which players must work together in order to achieve a team goal, but also offered classes which created a rock paper scissors type of gameplay. This encouraged users to play varied classes and also to use the classes in conjunction with one another in order to gain the greatest advantage.
Team Fortress Classic supports numerous types of play, with distinct objectives for teams of players to pursue. There are nine standard classes in Team Fortress Classic that a player can select. Each class is equipped with at least one unique weapon, and is often armed with a secondary weapon such as a shotgun or nailgun. In addition, all classes are armed with a melee weapon-usually a crowbar-as well as grenades with a variety of effects depending on the class a player has chosen. In escort levels, a single player can assume the role of a civilian, armed only with an umbrella (and but 50 health and no armor), and must be escorted by the rest of the team across the level.
Team Fortress was originally a 1996 QuakeWorld mod. Its developers were working on Team Fortress 2 as a standalone game, but later joined Valve Software and ported the original as a mod for Half-Life called Team Fortress Classic in April 1999. Despite the company's 1998 statement that Team Fortress 2: Brotherhood of Arms would be released "soon", the game remained in development of one form or another for eight years until its release on October 10, 2007, and had been on Wired magazine's top ten vaporware list every year since 2001.
Since Team Fortress Classic's release in 1999, Valve has introduced various changes into the game. The updates tweaked the game's balance and on occasion added new content, such as new levels. A particularly large update was released on June 8, 2000, which introduced several new levels and game modes and a new GUI menu interface, and optimized the game's network code for smoother, faster play. With this release, the game was renamed to Team Fortress 1.5. On March 13, 2001, the player models were redesigned. In 2003, the game was migrated into Valve's Steam system. Since then, a number of additional features were added. For much of its early history, Team Fortress Classic was second only to Counter-Strike as the most played and popular of online games.

Team Fortress 2 is a free-to-play team-based first-person shooter multiplayer video game developed by Valve Corporation. A sequel to the original mod Team Fortress based on the Quake engine, it was first released as part of the video game compilation The Orange Box on October 10, 2007 for Windows and the Xbox 360. A PlayStation 3 version then followed on November 22, 2007. The game was later released as a standalone package for Windows on April 9, 2008, and for Mac OS X two years later. Team Fortress 2 is distributed online through the Steam system, while retail distribution was handled by Electronic Arts. In June 2011, the game became a free-to-play title, supported by microtransactions for unique in-game equipment through Steam. The development of Team Fortress 2 is led by John Cook and Robin Walker, the designers who originally created the Team Fortress modification for Quake in 1996.
The game was announced in 1998, powered by Valve's GoldSrc engine, but has since been through various concepts and designs. In 1999, the game appeared to be deviating from its predecessors by pursuing a more realistic and militaristic style of gameplay, but the design metamorphosed over its nine-year development period. The final rendition sports cartoon style visuals influenced by the art of J. C. Leyendecker, Dean Cornwell and Norman Rockwell and is powered by the Source engine. The game itself revolves around two teams, each with access to nine distinct characters, battling in a variety of game modes set in evil genius environments.
The lack of information or apparent progress for six years of the game's original development caused it to be labeled as vaporware, and it was regularly featured in Wired News' annual vaporware list among other ignominies. Upon its release, the game received critical acclaim and several awards, being praised for its graphical style, balanced gameplay, comedic value and for its use of full character personalities in a dedicated multiplayer only game.
Like its predecessors, Team Fortress 2 is focused around two opposing teams competing for a principal objective. These teams, Reliable Excavation & Demolition (RED) and Builders League United (BLU), are meant to represent two holding corporations that between them secretly control every government on the planet. Players can choose to play as one of nine classes in these teams, each with his own unique strengths and weaknesses. Although the abilities of a number of classes have changed from earlier Team Fortress incarnations, the basic elements of each class have remained. The game was released with six official maps, although 25 extra maps, 9 arena maps, and four training maps have been included in subsequent updates. In addition, a number of community assembled maps have been released. When players join a level for the first time, an introductory video shows how to complete its objectives.
Team Fortress 2 is the first of Valve's multiplayer games to provide detailed statistics for individual players. They include the time spent playing as each class, most points obtained and the most captures or objectives achieved in a single life. Persistent statistics tell the player how he or she is improving in relation to these statistics, such as if a player comes close to his or her record for the damage inflicted in a round.
There are nine unique player classes in Team Fortress 2, categorized into offense, defense, and support roles. Each class has at least three weapons: a unique primary weapon, a common or unique secondary weapon such as a shotgun or pistol respectively, and a distinct melee weapon in keeping with the character, such as a liquor bottle for the Demoman, a kukri for the Sniper, and a fire axe for the Pyro.
Valve has stressed their focus on game balance when considering new improvements to the character classes. Every class has its own strengths and weaknesses which leads to reliance on other classes in order to be efficient. This forces gameplay into more strategic thinking and an increased utilization of teamwork than would be found if one class had inherent superior advantages. Each of the classes in the three categories have shared strengths and weaknesses, while each individual class also has its own advantages.
On June 23, 2011, Valve announced that Team Fortress 2 would become a free-to-play title; the core game could be enjoyed for free, while unique equipment, character outfitting, and the like would be available as microtransactions through the in-game store tied through Steam.
To promote the game, Valve has released an ongoing video advertisement series entitled "Meet the Team" since May 2007. Constructed using the game engine and slightly more detailed character models, the series consists of short videos on individual characters, displaying their personalities and tactics. The videos are usually interspersed with clips of the character in combat in the game

Day of Defeat is a team-based multiplayer World War II first-person shooter video game of the European Theatre of World War II.
Day of Defeat is a 3D multiplayer shooter that simulates squad-level infantry combat between the adversaries of World War II's European Theatre; the Allies or the Axis Powers. The goal is to complete various mission objectives.
Players can choose between the Allied armies (American and/or British armies, depending on the map) or the Axis armies. In Day of Defeat: Source there are only the American and German armies.
A round begins with two opposing teams starting simultaneously in their respective spawn area of a map. A round ends when one team accomplishes all of its objectives.
Player casualties become reinforcements which are supplied according to a timer. The reinforcements originate at spawn and can be composed of anywhere from 1 soldier to the entire team. The reinforcement timer is usually between 10-20 seconds, but this time may vary from server to server.
Like other Half-Life mods, Day of Defeat tracks each player's accomplishment in team objectives, how many enemies each player has eliminated and how many times each player has died. The game also tallies these statistics for the entire team; this reflects the team's score which is primarily based on objectives.
After many rounds, the game ends when a set time limit expires, and the team with the most objectives achieved is the winning team regardless of kills or casualties, except in the case where both teams have not achieved any objectives or are tied in the objective score. The scoreboard is displayed and the game is restarted with another map.
Day of Defeat maps do not always require that both teams have the same objectives. Some of the more popular maps have different objectives for each team.
Conquest Mode
Players can capture a flag by standing near the flag for a certain amount of time. Certain flags require more than 1 player for capture. Flags are presented as either uncaptured (Grey), Axis (Red) or Allies (Green or the Union Jack if the Allied team is British). Certain maps (dod_charlie) do not allow a captured flag to be recaptured by the defending team.
Destroy Target
Players destroy a target by first planting a bomb at the target. The bomb is obtained from the spawn area. This bomb can also be picked up from the body of dead comrades. To plant the bomb, the player has to just stand within the designated bomb area. Bombs once planted cannot be defused and will detonate in a sizeable explosion. In certain maps such as dod_jagd, players may destroy targets (tanks) using rocket launchers.
Capture Target
This is a variation of the capture the flag. Instead of a flag, a target (truck, airplane, or building) can be captured.
Capture Item
Players attempt to capture an item (secret documents) and return it to a designated location.
DoD began as a Half-Life 3rd party mod in 2000. Later, the DoD team joined Valve Software and produced a standalone version published through Activision. DoD (ver.1.0) was officially released in May 2003. It was converted over to the Steam delivery system in version 1.1. Steam is now required to play DoD. Day of Defeat: Source was released on September 26, 2005.
Day of Defeat features historical weaponry used during World War II.
Players may also drop their main weapon to pick up those left by dead soldiers or discarded by other players, thus Allied players can wield Axis guns and vice versa.
Day of Defeat maps muster scenarios of historical World War II battles requiring teams to control territory and complete objectives. Territorial control scenarios require the players to capture flags at important choke points throughout the map. Objective-based maps take players into battle for mission targets, such as a bridge or German Nebelwerfer (artillery) or any other various tactical targets. To achieve most tasks requires the players to use TNT charges at the objective. The many different possible objectives types include "clandestine missions", such as obtaining secret documents and returning them to headquarters.
Official DoD maps included with the game encompass scenes such as the infamous battle at Omaha Beach (dod charlie), streetfighting in the Italian city of Salerno during Operation Avalanche (dod avalanche), and a Glider Mission where the American 101st Airborne lands in a WACO Glider and has to destroy such objectives as a radio antenna and Flak 88 mm gun anti-aircraft gun (dod glider).
Day of Defeat maps offer the player the ability to blast through certain parts of the map to gain entry into new sections. This offers a twist to normal map strategies. The sections are normally marked with a crack in the wall, which can be opened by either planting a bomb or by shooting a rocket at it.

Day of Defeat: Source is a team-based first-person shooter multiplayer video game developed by Valve Corporation. Set in World War II, the game is an updated version of Day of Defeat, moving from the GoldSrc engine used by its predecessor to the Source Engine. The game was released for Microsoft Windows on 26 September 2005, distributed through Valve's online content delivery service Steam. Retail distribution of the game was handled by Electronic Arts.
Day of Defeat: Source is set in World War II, specifically the European Theatre in the year 1944. Players choose to join the forces of either the United States Armyor the German Wehrmacht and compete against each other in a variety of game modes. Players select from one of six classes to play as, each with its own role within the team. Player characters cannot take much damage, and in some circumstances can be killed by a single bullet, forcing players to make use of cover to stay alive. When a player character dies, that player starts a short countdown for reinforcements. When the timer runs out, the player and any friendly players killed in that time respawn into the game at their insertion point as the next wave of troops. All weapons in the game have realistic limits to their use: machine guns must be deployed to maintain accurate fire or to be reloaded, rocket launchers must be shouldered to be aimed and fired, sniper rifles are most accurate when used with the scope and grenades not "cooked off" before release may be easily fled or even thrown back by the opposition.
The game was initially released with four maps, although later updates have introduced five new official levels and eight community produced maps supported by Valve. The game's levels are based after real battles in the Allied campaigns in Italy, Sicily and France, such as the Falaise pocket or the beach landings of Operation Shingle at Anzio, as well as entirely fictional battles. Combat can take place in several environments, such as city streets, buildings and sewers. Each online game can sustain a maximum of 32 players.
There are two main game modes in Day of Defeat: Source: Territorial Control and Detonation. In Territorial Control Maps, players must fight for control of all strategic points on the map. The strategic points take various forms, such as a destroyed tank in a street or fields and buildings, and are designated by a flag in its vicinity, which displays the army colors of the team who controls the point. Points are captured by a certain number of team members surrounding the point, with it either capturing instantly or after a couple of seconds. Players on the other side can disrupt a capture by placing themselves within the capture area during the process or by killing the enemy players at the point. The first side to capture all the points wins the round.
The objective in a Detonation Level is to plant and detonate explosive devices on a number of enemy positions, which can consist of AA guns, tanks and armored cars. Some positions must be hit twice for them to be completely destroyed. Players can protect their positions by defusing the explosives before they detonate. In one variation of this game mode, one side has to defend their positions for a set amount of time, with the destruction of each piece of equipment giving the enemy team more time. The defenders win if they can hold their positions long enough for the time to run out, while the attackers win when all objectives have been destroyed. In the alternate version, both teams must attack the other's objectives while defending their own. The first team to destroy all of the enemy's equipment wins.
Both factions in Day of Defeat: Source have access to six classes. Each class is designed with specific combat circumstances in mind, so that teams must use teamwork to succeed. The weapons and equipment carried by the classes are based on the weapons used by both the US Army and Wehrmacht during World War II. Some of classes are armed with pistols-the American M1911 or the German Walther P38-while others are equipped with trench knifes or entrenching tools for melee combat. Grenades are carried by a number of classes, depending on their role in the game-riflemen are equipped with rifle grenades, the assault classes are armed with a single fragmentation grenade and a smoke grenade for providing concealment, while support classes have access to two standard fragmentation grenades. Riflemen are armed with their respective army's standard infantry rifle, and are designed for medium to long range combat, while the assault classes carry submachine guns which are only effective in close quarters. The support classes are designed for medium range combat, equipped with either the M1918 Browning Automatic Rifle or the StG44. Snipers are used for attacking enemy targets from long range, and are consequently armed with their army's standard bolt-action sniper rifle. Machine gunners carry machine guns to defend key locations on a level or to provide a base of fire for their team's advance. Machine gunners are required to deploy their weapons on bipods before firing in order to compensate for the machine gun's extreme recoil. The final class is armed with an anti-armor weapon, used in the game to displace enemy machine gun or sniper positions. This class is armed with either an M1 carbine or Mauser M712 to defend themselves with when moving.
Day of Defeat: Source was first announced for Microsoft Windows during the development of Half-Life 2, the flagship game of the Source engine, as one of several of the Valve Corporation's GoldSrc powered games to be remade on the new game engine.
The game was opened to an internal beta test soon after, which certain members of the Day of Defeat community were invited to join. The beta version of the game was shown as a straight conversion of the most recent version of Day of Defeat, at the time even including the same player and weapon models as the game's GoldSrc counterpart. Due to the response of the beta testers, significant changes were made to the gameplay, taking it away from being a straight conversion: the behaviour of weapons was altered and several classes from Day of Defeat were dropped entirely. Later media releases showed the revamped version of the game, including its new player and weapon models, as well as new additions to the game, such as rifle grenades and smoke grenades.
Day of Defeat: Source has been used by Valve as a platform for demonstrating several technologies in the Source engine. Day of Defeat: Source introduced a dynamic audio system that was limited to non-player characters in Half-Life 2. The sound of each weapon firing in-game is attributed with distance and occlusion variables, which are processed and then fed back to the player. Sounds far from the player lack higher frequencies and thus sound more like they naturally would, allowing for the actions of other players on a map to make up the ambient sounds for the level. The game was the first to incorporate Valve's high dynamic range rendering, predating the official demonstration, Half-Life 2: Lost Coast. Other effects were added post-release to make the game appear as if it were a World War II era film. The effects include motion blur, depth of field, film grain and color correction. Phong shading on the Source engine was added to Day of Defeat: Source with the major update in the second quarter of 2006.
To promote the game, Valve has produced three machinima trailers depicting the game in play. The trailers are themed around wartime propaganda news reports for both Germany and the United States. To convey this effect, the trailers make extensive usage of the Source engine's capabilities for film grain, color correction, motion blur and depth of field, as well as sepia toning.
Day of Defeat: Source was given a favorable reception upon release, receiving ratings of 80% and 81% from the review aggregation sites Metacritic and Game Rankings.

Portal is a single-player first-person puzzle-platform sci fi video game developed by Valve Corporation. The game was released in a bundle package called The Orange Box.
The game primarily comprises a series of puzzles that must be solved by teleporting the player's character and simple objects using "the handheld portal device", a device that can create inter-spatial portals between two flat planes. The player-character, Chell, is challenged by an artificial intelligence named GLaDOS (Genetic Lifeform and Disk Operating System) to complete each puzzle in the Aperture Science Enrichment Center using the portal gun with the promise of receiving cake when all the puzzles are completed. The game's unique physics allow momentum to be retained through portals, requiring creative use of portals to maneuver through the test chambers. This gameplay element is based on a similar concept from the game Narbacular Drop; many of the team members from the DigiPen Institute of Technology who worked on Narbacular Drop were hired by Valve for the creation of Portal.
The game's popularity has led to official merchandise from Valve including plush Companion Cubes, as well as fan recreations of the cake and portal gun. A sequel, Portal 2, was released in 2011, adding several new gameplay mechanics and a cooperative multiplayer mode.In Portal, the player controls the protagonist, Chell, from a first-person perspective as she is challenged to navigate through a series of rooms using the Aperture Science Handheld Portal Device (portal gun or ASHPD). The portal gun can create two distinct portal ends, orange and blue. The portals create a visual and physical connection between two different locations in three-dimensional space. Neither end is specifically an entrance or exit; all objects that travel through one portal will exit through the other. An important aspect of the game's physics is momentum redirection. As moving objects pass through portals, they come through the exit portal at the same direction as the exit portal is facing and with the same speed with which they passed through the entrance portal.
Chell and all other objects in the game that can fit into the portal ends will pass through the portal. However, a portal shot cannot pass through an open portal; it will simply fail or create a new portal in an offset position. If a portal of the same color as an existing one is created, the previous portal is destroyed. Moving objects, glass, special wall surfaces, liquids, or areas that are too small will not accommodate portals. Chell is sometimes provided with cubes that she can pick up and use to climb on or to hold down large buttons that open doors or activate mechanisms. Particle fields known as emancipation grills exist at the end of all and within some test chambers that, when passed through, close any open portals and disintegrate any object carried through. The fields also block attempts to fire portals through them.
Although Chell is equipped with mechanized heel springs to prevent damage from falling, she can be killed by various other hazards in the test chambers, such as turret guns, bouncing balls of energy, and toxic liquid. She can also be killed by objects falling through portals, and by a series of crushers that appear in certain levels. Unlike most action games, there is no visible amount of health; Chell dies if she is dealt a certain amount of damage in a short time period, but returns to full health fairly quickly. Some obstacles, such as the energy balls and crushing pistons, will deal this necessary amount of damage with a single blow, thus causing instant death.
Two additional modes are unlocked upon the completion of the game that challenge the player to work out alternative methods of solving each test chamber. Challenge Maps are unlocked near the halfway point and Advanced Chambers are unlocked when the game is completed. In Challenge Mode, levels are revisited with the added goal of completing the test chamber either with as little time, with the least number of portals, or with the fewest footsteps possible. In Advanced Mode, certain levels are made more complex with the addition of more obstacles and hazards.
The game features two characters: the player-controlled silent protagonist named Chell, and GLaDOS a computer artificial intelligence that monitors and directs the player. The only background information presented about Chell is given by GLaDOS; the credibility of these facts, such as Chell being adopted, an orphan, and having no friends, is questionable at best, as GLaDOS is a liar by her own admission.
Portal is Valve's spiritual successor to the freeware game Narbacular Drop, the 2005 independent game released by students of the DigiPen Institute of Technology; the original Narbacular Drop team is now employed at Valve.
The austere settings in the game came about because testers spent too much time trying to complete the puzzles using decorative but non-functional elements. As a result, the setting was minimized to make the usable aspects of the puzzle easier to spot, using the clinical feel of the setting in the film The Island as reference. While there were plans for a third area, an office space, to be included after the test chambers and the maintenance areas, the team ran out of time to include it.
The Weighted Companion Cube inspiration was from project lead Kim Swift.
The portal gun's full name, Aperture Science Handheld Portal Device, can be abbreviated as ASHPD, which resembles a shortening of the name Adrian Shephard, the protagonist of Half-Life: Opposing Force.
The popularity of the game and of its characters has led Valve to develop merchandise for Portal. Some of the more popular items were the Weighted Companion Cube plush toys and fuzzy dice. When first released, both were sold out in under 24 hours.
In January 2008, Valve released a special demo version titled Portal: The First Slice, free for any user using Nvidia graphics hardware as part of a collaboration between the two companies. The demo includes test chambers 00 to 10 (eleven in total).
Portal was first released as part of The Orange Box for Microsoft Windows and Xbox 360 on October 9, 2007, and for the PlayStation 3 on December 11, 2007.
Portal: Still Alive was announced as an exclusive Xbox Live Arcade game at the 2008 E3 convention, and was released on October 22, 2008. It features the original game, 14 new challenges, and new achievements. The additional content was based on levels from the map pack "Portal: The Flash Version" created by We Create Stuff and contains no additional story-related levels.
Portal was very well-received by critics. It was a favorite of The Orange Box, often earning more praise than either Half-Life 2: Episode Two or Team Fortress 2. It was praised for its unique gameplay and dark, deadpan humor.
A modding community has developed around Portal with users creating their own test chambers and other in-game modifications. The group "We Create Stuff" created an Adobe Flash version of Portal, entitled Portal: The Flash Version, just prior to release of The Orange Box that was well received by the community which they have since converted to a map pack for the published game. Many of the levels in this map pack have been incorporated into the standalone Xbox Live Arcade game Portal: Still Alive. Another mod, Portal: Prelude, is an unofficial prequel developed by an independent team of three that focuses on the pre-GLaDOS era of Aperture Science, and contains nineteen additional "crafty and challenging" test chambers. An ASCII Version of Portal was created by Joe Larson. An unofficial port of Portal to the iPhone using the Unity Game Engine was created but only consisted of a single room from the game.

Portal 2 is a first-person puzzle-platform video game developed and published by Valve Corporation. Like Portal, Portal 2 primarily comprises a series of puzzles that must be solved by teleporting the player's character and simple objects using the "portal gun", a device that can create inter-spatial portals between two flat planes. The game's physics allow momentum to be retained through these portals, which must be used creatively to maneuver through the game's challenges. Most gameplay elements of the original Portal were retained in the sequel, and more were added to Portal 2, including tractor beams, laser redirection, bridges made of light, and paint-like gels that impart special properties to objects they cover.
Within the single player campaign, the player returns as the human Chell, having awakened from stasis after many years. Chell must navigate the now-dilapidated Aperture Science Enrichment Center and its test chambers with the portal gun while the facility is rebuilt by the reactivated GLaDOS, an artificially intelligent computer that first appeared in Portal.
Portal 2 is a puzzle game presented from the first-person perspective. Players act as Chell in the single-player campaign and as one of two robots, Atlas and P-Body, in the co-operative campaign. All three can move, look, and interact with the environment. The character can withstand damage for a brief period but will die under sustained injury. There is no penalty for falling onto a solid surface, even at high speed, but falling into bottomless pits or pools of toxic liquid kills the player-character immediately. When Chell dies in the single-player game, the game restarts from a recent checkpoint; in the co-op game, the robot respawns shortly afterwards without restarting the puzzle. The goal of both campaigns is to maneuver the character(s) through the Aperture Science facility. While most of the game takes place in modular "test chambers" with clearly-defined entrances and exits, other parts occur in behind-the-scenes areas where the objectives are less clear.
Portal 2 also introduces paint-like gels that impart certain properties to a surface or object coated with them. Gelsare dispensed from pipes and can be transported through portals. Orange Propulsion Gel boosts the player's speed as they cross a surface, Blue Repulsion Gel allows them to bounce from a surface, and White Conversion Gel allows many surfaces to accept portals. Some surfaces, such as grilles, cannot be coated with a gel. Water can block or wash away gels, returning the surface or object to its normal state.
Portal 2 follows the player-character Chell after the end of Portal, in which she destroys the rogue artificial intelligence construct GLaDOS that ran the Aperture Science Enrichment Center where the game is set. In Portal's backstory, Aperture Science conducted experiments to determine whether human subjects could navigate dubiously safe "test chambers", until GLaDOS killed the scientists with a neurotoxin. The ending of the first game, retroactively patched just prior to the sequel's official announcement, shows Chell being dragged away from the remains of GLaDOS by an unseen figure with a robotic voice, later identified by writer Erik Wolpaw as the "Party Escort Bot". A promotional comic shows that an estranged Aperture Science employee placed Chell into suspended animation for an indefinite amount of time, in an effort to save her life.
After the success of Portal, which was originally an add-on product to the game compilation The Orange Box, Valve decided to make Portal 2 its own product. Work began almost immediately after the release of Portal. They committed more resources than for the first game; Portal had a team of seven or eight people, but Portal 2 had a team of 30 or 40.
Portal 2 received universal acclaim from reviewers on its release, resulting in an average score of 95 out of 100 according to review aggregator Metacritic; several reviewers identified Portal 2 as an early contender for "Game of the Year", while others called it one of the best games of all time. Prior to its launch, several critics had expressed concern that Valve might be unable to take the shorter, experimental, Portal from The Orange Box and make it into a full retail game, but upon release the game was widely considered to be as good as or better than the original.
Portal 2 has won the title of "Ultimate Game of the Year" at the 2011 Golden Joystick Awards, and ranked Second Place on Time's "Top 10 Video Games of 2011". Gamasutra, Eurogamer, Associated Press, and The Mirror listed Portal 2 as its Top Video Game of 2011. The game received twelve nominations including "Game of the Year" for the 2011 Spike Video Game Awards, the most of any title, and won for "Best PC Game", "Best Male Performance" (for Stephen Merchant), "Best Female Performance" (for Ellen McLain), "Best Downloadable Content", and "Best Multiplayer Game".

These were the elements that were found in the DOTA 2 client:

/src/game/server/ep3/weapon_icegun.cpp
/src/game/server/ep3/weaponizer_concrete.cpp
/src/game/server/ep3/weaponizer_liquid.cpp
/src/game/server/ep3/weaponizer_metal.cpp
/src/game/server/ep3/weapon_flamethrower.cpp

There were also additional code found like: Here's also some code labelled "sob", with mentions of "func_nebula", "sob_server_ship_system" and "sob_flightplan".

Over at the Steam Forums, a user by the name >StickZero has found something in the Alien Swarm SDK that could be evidence that Half Life 2: Episode 3 is in development. If you open the Alien Swarm SDK, place an info_node_hint and check the hint options you will see Aperture Nest, Blob Brain etc. Tthis may well be the proof Half Life fans have been waiting for to show that Episode 3 is indeed in development.

With the last expansion for Half Life 2 getting released back in 2007, Valve have left us out in the cold for a little too long. Fingers crossed the long wait for Episode 3 or Half Life 3 will be worth it, and that Valve are hard at work making the next instalment the best yet. But what do we know of the next game in the classic series, and what kind of improvements would we want made anyway?
So what do we know of the expected improvements for the next Half Life? In short, we know nearly nothing. We have seen a few concept images that you can see strewn throughout the article. These, in conjunction with various interviews with Valve co-founder Gabe Newell, imply that the tone for the next Half Life game will be darker and possibly more horror orientated. This could be a potentially refreshing new direction for the series. After all, aside from the fantastic level in Ravenholm, Half Life 2 largely lost the isolation and horror aspects that were a staple of the original Half Life. More Headcrabs would definitely be a good start toward this brave new direction. The shots also show the sunken Aperture science research ship, The Borealis, possibly alluding to a potential Portal reference?
The plot for the next instalment is also a great uncertainty. If we do indeed get the final episode for Half Life 2 we can expect to see the narrative continue following Gordon Freeman from where he left off in the last game, yet if a third core Half Life game is on the cards the story could theoretically go anywhere. It is unlikely we will see a new protagonist considering the popularity of Gordon Freeman among fans, though Half Life 3 could take find its narrative taking a serious chronological step out from the rest of the series as Half Life 2 did back in 2004. What has been an interesting development is the news that Gabe Newell has been conducting research into sign language as an "excuse to build the technology for signing." Though he describes it as a mere technological exercise for an unspecified game, there could well be a chance that a deaf character will be incorporated into future Half Life titles in order for Valve to put this research to good use. Newell has also hinted at a deaf character in the Half Life universe who Alex was smitten with before her encounters with Gordon Freeman. Is there going to be a romantic clash between our protagonist and this new character in a subsequent Half Life game? Regardless, it is nice to see Valve investigating avenues that will open their games up to demographics that are often unfairly considered subsidiary in our industry.
Though we might not necessarily know much of what Valve have in store for the Half Life series, that won't stop us from making unreasonable demands and speculations on what should be included. The one major flaw that seemed to dog the episodic instalments for Half Life 2 was the issue of content. We weren't exactly expecting a vast campaign length for the episodic DLC but, when you consider how long Valve took developing the Half Life 2 add ons, there wasn't much excuse for their brevity. Whether we get an Episode 3 or a full blown Half Life 3, Valve need to show us that the time spent developing it will be worth it with a longer campaign.
n terms of innovations there isn't a lot the next Half Life needs to add, aside from the obvious story expositions. It would be interesting to see though if Valve decides to utilize a new version of the source engine to coincide with the release of a new Half Life. Considering Half Life 2 introduced us to the source engine and the Steam digital distribution platform, it isn't off the cards that a new Half Life would also introduce some new Valve goodies. Whether it be a major Steamupdate or a totally new source engine, it would be a real game maker for the next Half Life sequel.
In truth there isn't much to request in terms of new features for Half Life Episode 3. We could make the natural speculations about new weapons and levels but, with what little we know about the game's direction, it is unlikely that this would be a particularly fruitful exercise. Instead fans are looking for just a little bit more of the same Half Life action we know and love. Half Life is a franchise that is well enough established to the point where we all just want to know what happens next, and to see what Valve are going to come up with. But when can we expect to see more of the series?
We'll just have to look forward......maybe next year...

Its been a long time since the last episode of Half Life 2 was released. But now, in what seems to be a concept art from Episode 3 has surfaced on the internet. It Is still not sure if this is original or not, but it is still investigating....

'We are not done with Gordon Freeman's adventures'- Valve

AusGamers asked Valve's marketing boss Doug Lombardi in a video interview- ""Will we ever see [more >Half-Life]?"
To which Lombardi replied by saying- "You will ever see it, yes. We are not done with Gordon Freeman's adventures. I have nothing other than that to tell you today, but hang in there with us."

On Thursday, December 1st, Chandana Ekanayake, part of Seattle-based game developer Uber Entertainment, saw a Valve employee wishing to remain anonymous, wearing a t-shirt saying "Half-Life 3", with an icon similar to the Half-Life 2 logo. The employee apparently "knew as much about Half-Life 3 as we do, which is absolutely nothing." Marc Laidlaw confirmed that "the T-shirt was real", but refused to comment further.

A Steam page has popped up for Counter-Strike: Global Offensive, and it's full of new screenshots. It looks as though CS: GO has received a substantial visual upgrade over its predecessors. Head below for shots of men, often holding guns, standing and shooting each other in some reworked versions of classic CS maps.

http://store.steampowered.com/app/1800/

Recently on the Internet have appeared new information about the new Counter Strike: Global Offensive.

It seems that the beta version of the game is available for download. However, to download the game you must fill out a Survay. on a Steam. After that you will receive a CS:GO Beta beta key from valve. Valve announced that they have added 5000 players already. Also, additionally the 5000 players selected have received a gift pass to give the CS:GO Beta beta to one of their friends. So if you aren't one of the lucky player ask maybe one of your friends already got a key.