Half-Life 2

Half-Life 2 is a first-person shooter video game and the highly-anticipated sequel to Half-Life, developed by Valve Software. It was released on November 16, 2004, to very positive reviews, following a protracted five-year development cycle, during which time, the game's source code was leaked to the internet. This title featured the advanced Source game engine, coupled with a heavily modified version of the Havok physics engine, and was critically acclaimed for ground-breaking improvements in animation, graphics, A.I. and physics. In the two months following its release, it sold over 1.7 million copies, but sales over Valve's Steam content delivery system were not disclosed.

A CD-ROM demo was later made available in December 2004, at the website of graphics card manufacturer ATI, who teamed up with Valve for the game. An Xbox version was released on the November 15, 2005.

Platinum
On February 1, 2007, Half-Life 2: The Platinum Edition was released for the PC. The Package included Half-Life 2, Half-Life 2: Deathmatch, Counter-Strike: Source, Day of Defeat: Source, and Half-Life 2: Aftermath (which would later be renamed "Half-Life 2: Episode One").

Half-Life backstory
The original Half-Life largely took place at a remote underground laboratory called the Black Mesa Research Facility. In the course of conducting an experiment, researchers at Black Mesa accidentally cause a "resonance cascade", opening a doorway to an alien world (Xen) and releasing a flood of strange and deadly creatures. The player takes the role of Gordon Freeman, one of the research scientists; the player guides him in his attempt to escape the facility. Half-Life 2 picks up the story an indeterminate number of years after the Black Mesa incident in 'City 17', which seems to be in Eastern Europe.

Plot
At the start of the game, the mysterious G-Man speaks to Gordon Freeman. Gordon then finds himself riding a train into City 17, unarmed and without his HEV suit. Details begin to slowly emerge: City 17 is under the rule of a totalitarian Administrator named Dr. Breen, the former administrator of the Black Mesa Research Facility. Breen is merely a puppet ruler, carrying out the will of the aliens known as the Combine. It seems that the massive energy discharge caused by the "resonance cascade" was enough to attract the attention of the Combine. Soon after, they mounted a brutal assault on humanity in which the forces of Earth were completely overwhelmed in just seven hours (which is, appropriately enough, referred to as the Seven Hours War). The Combine now has near-absolute control of the entire planet, with only a few pockets of human resistance remaining. Dr. Breen enforces his rule (and, by extension, the Combine's rule) through armies of intimidating "Civil Protection" units (also called "Metropolice" or "Metrocops") and Combine soldiers (referred to as the Overwatch).

Chapters
The gameplay, like the first Half-Life, is divided into titled chapters:


 * Point Insertion - Gordon arrives weaponless and with no HEV suit, meeting up with old friend Barney Calhoun from Black Mesa. Barney has infiltrated Civil Protection, for the resistance.


 * "A Red Letter Day" - Gordon meets Alyx Vance (daughter of Dr. Eli Vance). Alyx takes him to Dr. Isaac Kleiner, Gordon's MIT mentor and Black Mesa colleague. Kleiner attempts to teleport Gordon to Eli's laboratory, Black Mesa East, at the city's outskirts, but Dr. Kleiner's pet headcrab "Lamarr" wrecks the machine. Gordon must find another way to reach the lab.


 * Route Kanal - While navigating the city's canals, Gordon finds resistance bases populated by both humans and Vortigaunts, who are now allies. After being helped through an underground railroad system, Gordon is provided an air boat, allowing him greater expediency.


 * Water Hazard - The air boat is spotted by the Combine and pursued by a hunter-killer assault helicopter. At another resistance base, a Vortigaunt affixes a weapon to the craft capable of downing the 'copter.


 * Black Mesa East - Gordon arrives at the lab and meets Dr. Judith Mossman. Alyx gives him a weapon called the Gravity Gun and instructs him on its use. Suddenly the lab is attacked by the Combine, forcing Gordon to escape along an old tunnel leading to Ravenholm.


 * "We Don't Go To Ravenholm..." - Gordon quickly discovers why Ravenholm was abandoned: the town has been overrun with headcrabs and "zombies". Father Grigori, a slightly-insane priest and likely the last human resident of Ravenholm, helps him survive the deadly town and escorts him to an abandoned mine which eventually leads to the dockyards outside City 17.


 * Highway 17 - Gordon finds another resistance base under assault by Combine troops. Alyx tells him that Eli has been captured and is being held in Nova Prospekt, an old maximum-security prison. Gordon travels the coast road in a dune buggy towards Nova Prospekt. The journey is made more difficult by the fact that it's spawning season for the insect-like antlions, which swarm the area.


 * Sandtraps - Gordon arrives at the Lighthouse Point resistance base and must continue the journey to Nova Prospekt on foot. Antlions lie hidden underground, emerging to attack at the slightest vibration. Gordon must move across rocks and avoid the loose sand that alerts them. After narrowly defeating an enormous "Antlion Guard", Gordon is given bugbait: a gland filled with pheromones that pacifies the smaller Antlions.


 * Nova Prospekt - Finally reaching the old prison, Gordon searches within for clues to Dr. Vance's whereabouts. The antlions' assistance helps to even the overwhelming odds against him.


 * Entanglement - Gordon joins forces with Alyx again, and together they find both Eli and Dr. Judith Mossman, who is apparently a Combine agent. While distracted by a Combine assault, Mossman teleports herself and Eli into the Citadel, the Combine's base of operations. Gordon and Alyx barely manage to teleport themselves to Dr. Kleiner's lab before the teleporter explodes.


 * Anticitizen One - A strange malfunction in the equipment has caused them to arrive at Dr. Kleiner's lab a week after they teleported. Meanwhile, Gordon's struggles against the Combine have brought new life to the resistance, plunging City 17 into chaos. Resistance fighters led by Gordon travel towards the Citadel to free Dr. Vance while Alyx helps Dr. Kleiner escape the lab.


 * "Follow Freeman!" - After rescuing Barney, who has been pinned down by snipers, Gordon shuts down a suppressor field blocking access to the Citadel. A pack of incredibly powerful Combine war-machines, the Striders, attack until they are finally destroyed by RPG fire.


 * Our Benefactors - Gordon enters the Citadel through an underground passage. Faced with a dead end, he is forced to enter a rail-driven containment apparatus. After a long trip through the Citadel, all his weapons are destroyed by a Dark Energy-powered "confiscation field". However, the Gravity Gun survives (probably due to its zero-point nature) and is made incredibly powerful. It can now manipulate organic matter, instantly killing Combine forces, and its lift strength is greatly increased. Armed with only the new Gravity Gun, Gordon wreaks havoc upon the Citadel until he is again faced with a dead end. Once more, the only way to progress is to voluntarily enter a containment apparatus.


 * Dark Energy - The device brings him face-to-face with Dr. Breen, who takes the Gravity Gun while Gordon is immobilized. Dr. Judith Mossman is with Breen, and he summons Eli and Alyx, who are being held in similar devices. As Breen threatens Gordon, Judith finally turns against him: she had only "betrayed" the resistance to get an opportunity to infiltrate Breen's inner circle. He manages to escape and flees towards a huge teleporter that will take him to the Combine's world. Freed, Gordon and Alyx pursue him and destroy the teleporter, triggering a massive explosion.

Notes on the narrative
Two distinctive elements from the original Half-Life are preserved: Gordon Freeman never speaks, and the entire game is viewed through his eyes. Some players have complained about these holdovers, since they effectively limit how much of the backstory is explained. The lack of cutscenes also mean that the player never sees what happens or has happened in Gordon's absence. Additionally, it would seem natural for Gordon to have a great deal of curiosity as to what has happened since the Black Mesa incident. Although these are certainly intentional devices on the part of Valve Software, some feel that it is very frustrating to only learn the story in small bits and pieces throughout the game. It could be said in Half-Life that the player's bewilderment is meant to mirror Gordon's during the chaotic events following the resonance cascade and alien invasion. By the opening of Half-Life 2, however, Gordon has proven that he can survive in a strange and hostile environment, and should therefore be at least somewhat more level-headed and inquisitive.

In any case, it's not clear to what extent Gordon exists as a separate character outside of the player's influence. Since the start of Half-Life, Valve have made sure that the player's and Gordon's experience are one and the same. Gordon may be nothing more than an empty vessel for someone else (i.e. the player) to inhabit. Many of the Vortigaunts' enigmatic comments seem to indicate this, the most prominent one being: "Far distant eyes look out through yours"

Adding to the sense of confusion is the fact that while most of Gordon's former co-workers from Black Mesa have visibly aged in the interim, Gordon has (presumably) not; however, only a few passing references are ever made regarding this. (The game never specifies how many years have passed between Half-Life and Half-Life 2, but many players agree that it is likely close to 10 years.) Fans have speculated that Gordon has been kept in stasis during his absence, and this is reinforced by the presence of a strange "interdimensional tram ride" that Gordon finds himself on at the end of both Half-Life games. Another cited explanation is that Gordon has been transferred using a "slow teleport", similar to the one discovered by the player at the end of the Nova Prospekt chapter.

The ending of Half-Life 2 is also very similar to that of the original: after completing a difficult task against overwhelming odds, Gordon is "extracted" by the G-Man, wielding incredible but unexplained powers. The player is smugly congratulated and told that further assignments should follow. The fate of many of the major characters, such as Alyx, Eli, and Judith, is unexplained. Very few, if any, of the questions raised by Half-Life are answered, and several new ones are presented. Some players have also complained that they expected more insight into the identity and nature of the G-Man. (These complaints, of course, only prove that the game's designers have successfully garnered interest in the series' continuation, whether through further sequels, or expansion packs such as Half-Life 2: Aftermath, which later became Half-Life 2: Episode One.)

Setting
The general theme and setting of Half-Life 2 incorporates many distinctly Orwellian elements, along with at least several more concepts borrowed from other canonical works of dystopic or post-apocalyptic fiction. In what is now seen as characteristic style, these in-game details are left to the player to discover and consider, as opposed to being deliberately and overtly projected. These include:


 * A rigid social hierarchy, protected and facilitated by a set of rules demanding conformity and obedience. Interaction between various human, trans-human, Combine and Xen life-forms are strictly regulated, and disregard for these is perceived as a threat to stability and balance.


 * Widely-distributed state propaganda (such as the "evolution" posters seen at certain points in City 17) that encourages citizens, from a moral standpoint, to sacrifice personal ideals in favour of submission and assimilation, for what leaders believe to be a common and noble end. Uniform clothing is adopted, people are herded into public hostels (usually with poor standards of living), and individualistic ideas (such as private ownership) are shunned. Citizens are encouraged to report 'anticivil' behaviour. The community is thus given priority over the person. Where 'gentler' measures to push such changes are met with resistance, harsher coercive tactics are employed which range from routine raids and beatings to long-term incarceration (sometimes in political prisons such as Nova Prospekt) or execution, in complete ignorance of basic rights.


 * Apart from persuading the people to abandon introspection and independent thinking, the ruling party also takes measures to alter or eradicate certain physical and mental states, in order to make minds more malleable, by installing technology for that specific purpose. In Half-Life 2, it is reported that The Combine have been inserting chemicals into drinking-water that cause memory lapses. Also, all movement is restricted via suppression-fields, barricades and gates requiring passcards. A halt is put to human procreation, the subject of a letter written to Dr. Breen by a "concerned citizen". The Overwatch system itself, a vast and seemingly self-aware communications network, is one of the primary methods of monitoring citizen activity.


 * A commonly-identifiable figurehead or chief acting as icon and representative of the system, backed by forces which choose to act in a secretive and under-handed manner where they see an advantage in it (this is most often associated with George Orwell's Thought Police). The icon cannot be said to represent the true nature of the system, and is often a cover (compared with George Orwell's Big Brother). These notions are reinforced during the course of the game, at times when the player witnesses Dr. Breen's public broadcasts from television sets or larger PA systems, when Civil Protection units attempt to contain city populations, or when Combine soldiers launch assaults on rebel outposts.


 * Deep-rooted fears about the unexplored world that lies outside of the state's domain. These may be instilled in the people to induce a sense of attachment to the system, or they may be genuine fears brought about by the deterioration or complete destruction of the physical territories beyond the state's borders. It may be argued that both apply in Half-Life 2, with emphasis on the latter, since the regions of Earth outside of the renamed cities have become dangerous and uninhabitable (except for the rebel forces, who have little choice) following the Seven Hours War and its 'fallout'.


 * A lexicon or functional language employed by the state, and its various agencies and sub-departments (in some cases, also by the citizens themselves), that is somehow alien to or irreconcilable with natural human language (compared with George Orwell's Newspeak). This may be considered a specific example of the culture-change measures outlined previously. A general impression of the Combine's rigid, totalitarian approach to law-enforcement may be derived from the public addresses delivered by the Overwatch system, using standard Overwatch jargon. An example follows: Individual... you are convicted of multi anticivil violations. Implicit citizenship revoke. Status: malignant.

Enemies
Many familiar enemies from Half-Life return in this game, such as the Headcrab, Barnacles, and Headcrab zombies, but the majority of the game is spent fighting the Combine, who wield large military forces against Gordon and the people of City 17. Also new to Half-Life 2 are Antlions, who act as both friend and foe during the game.

Allies
Although Gordon battles through much of Half-Life 2 alone, like Half-Life he is assisted in several places by friendly allies. For the most part these are human members of the Resistance, but Gordon is also helped by vortigaunts and (as noted above) Antlions. At several key locations, Gordon also meets up with, and fights alongside, more significant NPCs like Alyx Vance, Barney Calhoun and Alyx's robot, Dog.

Weapons
Many of the weapons featured in Half-Life 2 were carried over from Half-Life, which include the crowbar, shotgun, .357 Magnum revolver, and rocket launcher, although new ones are introduced, such as the Combine's Pulse Rifle, resistance built crossbow, and pheropods. The main weapon used is the Gravity Gun, which can pick up and throw objects and also hurt small enemies from its blast.

Multi-player

 * For more information, please see "Half-Life 2: Deathmatch".

When Half-Life 2 was released, its only multi-player component was Counter-Strike: Source. On November 30, 2004, Valve released the Half-Life 2: Deathmatch component along with the full SDK as a free download to all Half-Life 2 owners.

Half-Life 2: Deathmatch currently has seven "official" maps, some of which are based on areas from the single-player game: "dm_overwatch", "dm_lockdown", "dm_steamlab", "dm_underpass", "dm_powerhouse", "dm_resistance" and "dm_runoff". The map "dm_overwatch" is based on the single-player chapter "Follow Freeman!", while "dm_lockdown" is based on the Nova Prospekt chapter. The "dm_steamlab" map is an original that is loosely based on the Half-Life: Deathmatch map "datacore", while "dm_runoff" was inspired by the popular Half-Life: Deathmatch map "dm_crossfire". Valve also ran a map-making contest within the community, announcing the winners in placement order as "dm_underpass", "dm_resistance", "dm_powerhouse",with "dm_avalon" as an honourable mention.

The map "dm_steamlab" was released on February 17 2005, along with three new weapons: the Crowbar, the Stunstick and the S.L.A.M. The S.L.A.M. is a mine-like device, functioning in the same way as a proximity mine. It can be attached to walls, where it emits a laser beam, which when broken will detonate the mine. S.L.A.M. mines can also be thrown and detonated at will by the player using the secondary fire. Both the Stunstick and Crowbar behave as they did in the single-player version of the game.

The goal of Deathmatch is for the player to kill as many other players as possible, using a variety of means. The player spawns with a gravity gun, pistol, sub-machine gun and grenades. All weapons aside from the pheropods (also known as bugbait) are available to be collected around the maps. Players can be killed by gunfire, explosions, or through contact with physics objects travelling at high speeds.

Some players have expressed disappointment in Half-Life 2: Deathmatch, specifically concerning the Gravity Gun. The seven official maps for Half-Life 2: Deathmatch are filled with objects which can be carried by the Gravity Gun, leading to their near-exclusive use. This is compounded by the damage these items can deal on contact with players, which is arguably far greater than any other conventional weapon. Instead of being deathmatch, some players argue, Half-Life 2: Deathmatch is an exercise in "lifting and chucking". The counter to the incredible power of the Gravity Gun is the relatively slow speed of its projectiles; indeed, the argument is not dissimilar to abuse hurled at players who camp with sniper rifles or RPG's. It is common for a player to immediately blame a factor beyond his or her control for a defeat.

Building barricades is another deathmatch strategy that has proved controversial. By using the Gravity Gun to place large amounts of objects in chokepoints (such as stairs or tunnels) leading to strategically important locations, the player defending the barricade is given a huge advantage over his opponents. Dealing with the barricades themselves is simple enough, but the distraction they provide is enough to render a player highly vulnerable against opponents. For example, the most popular camping spot in "dm_overwatch" is near the actual overwatch, a Combine lookout post. This spot is easy to defend since players can block the only way leading to the overwatch with objects. This results in a stalemate in the favour of the camper, who can indefinitely "camp" the overwatch using a RPG that is conveniently placed nearby.

Cuts
A book called Half-Life 2: Raising the Bar revealed that the Nova Prospekt chapter was originally much longer, but was subsequently cut down to just one scene. Many hints and conversations that answered several questions players have asked were also cut. Raising the Bar shows scripts of these scenes, screenshots, and even fully rendered models, indicating the section was cut late in development. Parts of it survive as glimpsed scenes during the last section of the released game.

Promotional shots and gameplay videos that were released before the game became publicly available showed parts of these scenes, and also showed enemies which do not appear in the final game, such as a hydra-like enemy. The hydra was apparently cut because its AI proved troublesome: it looked great when attacking NPCs, but it was not felt to be a convincing enemy for the player.

It remains unknown if the cut Half-Life 2 scenes will eventually be completed and released, or if they are lost forever. A removed section of the original Half-Life was eventually released as the Half-Life: Uplink demo; it is possible that removed sections of the sequel will be seen in an expansion pack.

Game engine
For Half-Life 2 Valve developed a new game engine called Source, which handles the game's visual, audio, and AI elements.

Additionally, when coupled with Steam, the engine can be easily upgraded to include many new graphical technologies. One such example is high dynamic range imaging, and Valve released a Half-Life 2 level called "Half-Life 2: Lost Coast". Half-Life 2: Lost Coast is free with a purchase of any Source-based video game. The purpose of Half-Life 2: Lost Coast was to show off the Source engine's new HDR (High Dynamic Range) lighting.

Steam content delivery system
Integral to Half-Life 2 is the Steam content delivery system developed by Valve Software. This allows customers to purchase games (or any other software) straight from the developer and have it downloaded directly to their computer. This system also allows "micro updates" to games - games are continually updated and only the most recent version is allowed to be run. This makes it much harder to hack the game to introduce cheats or to play online with an unauthorized copy. All users playing the single player game must also have an account on the Steam servers to do so. Steam can also be used for finding and playing multi-player games and features an integrated server browser and friends list.

A 1 GB portion of Half-Life 2 became available for pre-load through Steam on August 26, 2004. This meant that customers could begin to download encrypted game files to their computer before the game was released. When the game was released at retail, customers were able to pay for the game through Steam, unlock the files on their hard drives and play the game immediately, without having to wait for the whole game to download. The pre-load period lasted for several weeks, with several subsequent portions of the game being made available, to ensure all customers had a chance to download the content before the game was released.

Controversies and criticisms
Half-Life 2 has been the subject of many problems and controversies since it was developed and subsequently released. A short list highlighting some of them is listed below.

Pre-Release

 * A source code leak from Valve's internal network in early September 2003, through the exploitation of bugs in Microsoft Outlook. Several people were subsequently arrested in June 2004, in suspicion of involvement in the source code leak.


 * A Beta leak at roughly the same time as the source code leak, which revealed the unfinished game to a number of users in the Internet, and was also the origin of the "physgun" weapon - a tool which could be used to interact with the physics objects in the game, such as ragdolls, as well as to weld them together.


 * A going gold hoax, which was announced using a stolen account of a Valve employee, on August 27, 2004.


 * A legal battle between Vivendi Universal Games (VUG) and Valve Software over the distribution of Half-Life 2 to cyber cafes, which was revealed to the public on September 20, 2004. The two parties eventually announced a settlement agreement on April 29, 2005, stating that:
 * The authority of distributing cyber cafe licenses are to be handed over to Valve from VUG (and Sierra), and licenses granted by VUG and Sierra to cyber cafes prior to the agreement are revoked.
 * VUG would cease distributing all retail packaged versions of Valve games by August 31, 2005.

Post-Release

 * The requirement for all legitimate Half-Life 2 users to create an account on Steam. This meant that anyone without internet access was effectively barred from registering and playing the game. Although a majority of players had internet access, it still affected a significant number of prospective consumers (However, a cracked version of the game which did not require Steam or a CD appeared on the Internet on the same day of the game's release). Also reported by some users was the hours-long wait to create an account in Steam (which normally only took seconds).


 * Shortly after the release of Half-Life 2 on November 16, 2004, many who had purchased the game through conventional retail channels or through Steam initially found themselves unable to play the game they had bought, as the Steam authorization servers were unable to smoothly process the high load.


 * The "No Counter-Strike" install error, which produces an error approximately 80% of the way into the installation procedure if a user does not wish to install Counter-Strike: Source. Note that Counter-Strike: Source can be removed after installing Half-Life 2 with Counter-Strike: Source, and the problem was not encountered by all users.


 * Reports of auto-save crashes and audio stuttering from some users. Patches were released to address these problems.


 * An update released on November 30, 2004, which inadvertently prevented scores of customers from launching the game. A minor update was quickly launched to resolve the issue. The update also added the multi-player Half-Life 2: Deathmatch, which had been noticeably absent from the original release.


 * Valve also released a Steam update on December 10, 2004 that solved the "disc in drive incompatibility error" by removing the Securom disc check routine. This change also allowed users to play the game without the game CD or DVD in their drives.


 * The alleged effect of motion sickness during game play, suspected to be caused by the game's narrower field of view. Valve's Bill Van Buren responded by concluding that no motion sickness was found during testing of Half-Life 2 (and its Source counterparts), but acknowledged that motion sickness during game play had happened during earlier development of the game, when "driving the buggy and the airboat... especially the airboat". However, he added that "some people still do experience some motion sickness effects from long stretches in the vehicles". Others attribute the motion sickness to the default refresh rate setting of 60 Hz.

Mods and expansions
There are several mods developed by Half-Life 2 mod teams. These include partial conversions which allow players to manipulate the physics engine or control Striders; mods which expand the story from different points of view; total conversions which introduce completely new settings; and multi-player mods. Several mods are listed in the article Half-Life 2 mods.

Half-Life 2: Episode One
Half-Life 2: Episode One, formerly known as Half-Life 2: Aftermath was the first official expansion pack for Half-Life 2. It picks up right at the end of "Half-life 2", with the core of the citadel at near-collapse. The vortigaunts show up to rescue Alyx, and pull you from the G-Man's grasp. However, it appears that they do not get you far enough away, and you wake up in a pile of rubble, being woken up by Dog. The rest of the game revolves around you and Alyx escaping the city. Eventually, you and Alyx make it out on a train, but just after leaving the city limits, the citadel explodes with a blinding light, followed by the credits.

Half-Life 2: Episode Two
Half-Life 2: Episode Two picks up at the end of Episode One, in the wreckage of the train. You and Alyx escape the wreckage just before a portal storm collapses the bridge and smashes what was left of the train.