Half-Life: Alyx is a 2020 virtual reality (VR) first-person shooter developed and published by Valve. Between the events of Half-Life (1998) and Half-Life 2 (2004), players control Alyx Vance on a mission to seize a superweapon belonging to the alien Combine. Players use VR to interact with the environment and fight enemies, using "gravity gloves" to manipulate objects, similarly to the gravity gun from Half-Life 2. Traditional Half-Life elements return, such as physics puzzles, combat, exploration and survival horror aspects.
The previous Half-Life game, Episode Two, was released in 2007. After abandoning plans for a third Half-Life episode, Valve began experimenting with VR in the mid-2010s, recognizing the demand for a large-scale VR game. They experimented with prototypes using their various intellectual properties, such as Portal, and found that Half-Life best suited VR. Alyx entered full production using Valve's new Source 2 engine in 2016, with the largest team in Valve's history.
Alyx was released for Windows on March 23, 2020, with support for most PC-compatible VR headsets. It received acclaim for its graphics, voice acting, writing, and atmosphere, and was cited by some as VR's first killer app. Valve released a Linux version in May 2020.
Half-Life: Alyx is a virtual reality (VR) game that supports all SteamVR-compatible VR headsets, which include the Valve Index, HTC Vive, Oculus Rift, Oculus Quest (wired through Oculus Link, or wireless using Virtual Desktop) and all Windows Mixed Reality headsets. As the gameplay was designed around VR, Valve stated there were no plans for a non-VR version. Half-Life: Alyx also supports user mods via the Steam Workshop. Valve's Robin Walker anticipated that fans would modify the game to allow it to be played without VR equipment, adding that Valve was curious to see how players would react to this version. Tyler McVicker of Valve News Network discovered a pre-release build of the game mistakenly leaked on Steam that included non-VR developer tools, allowing interactions such as picking up objects and firing weapons. However, most of the game's basic interactions such as pressing buttons or filling Alyx's backpack could not be completed with the "use" key. McVicker concluded that unless a modder found a way to completely change how the player's actions affected the game world, it was impossible to play the entire game with a non-VR control scheme.
The game takes place before the return of Gordon Freeman in Half-Life 2. Players control Freeman's ally Alyx Vance as she and her father Eli Vance fight the Combine, an alien empire that has conquered Earth. Designer David Speyrer said Alyx was not an episodic game or side story, but "the next part of the Half-Life story", around the same length as Half-Life 2. Players use VR to get supplies, use interfaces, throw objects, and engage in combat. Like the gravity gun from Half-Life 2, the gravity gloves allow players to manipulate gravity. Traditional Half-Life elements such as exploration, puzzles, combat, and story are there. Every weapon can be used one-handed, as Valve wanted players to have a hand free to interact with the world at all times. While the game is primarily a first-person shooter, it adds elements of the survival horror genre, as health and ammo are more scarce, and it includes surprise frightening encounters.
As with any first-person shooter, the player has the ability to move Alyx across a level. This can be done with VR room scale support if the player has sufficient space, physically moving around to move Alyx around in-game. Alternatively, the player can opt to use analog sticks on the VR controllers to move Alyx (a method common to most video games), to use a "teleportation" method where the player points in-game to where they want to move and the game jumps Alyx there, or an intermediate mode where, after selecting the destination point, the game glides Alyx there, smoothing the transition and giving the opportunity for the player to look around during it. In the case of the teleportation option, the game still simulates the movement even though the action appears instantaneous, and Alyx may die if attacked or move from too great a height.
Half-Life: Alyx takes place five years before the events of Half-Life 2. After Alyx (Ozioma Akagha) and her father Dr. Eli Vance (James Moses Black) are captured by the Combine, fellow Resistance member Russell (Rhys Darby) rescues Alyx and warns her that Eli will be transported to Nova Prospekt for interrogation. Alyx ventures into the Quarantine Zone, an area outside of City 17 contaminated with alien life, to intercept the train carrying Eli. Along the way, she meets an eccentric Vortigaunt (Tony Todd) that alludes to Eli Vance suffering an untimely death in the future.
Alyx derails the train after making her way through the Quarantine Zone, and the Vortigaunt rescues Eli from falling from the wreckage. Eli warns Alyx that he learned that the Combine are storing a super-weapon held in a massive "Vault" in the Quarantine Zone while he was in custody. He instructs Alyx to find the Vault and steal its contents before the Combine can transfer it to a safer location. She ventures through the Quarantine Zone, contending with various species of Xen aliens and Combine soldiers on her way to the Vault. Alyx is able to shut down a power station keeping the Vault afloat in the sky, discovering that each station contains an enslaved Vortigaunt forced to channel its energy to the Vault. The Vortigaunt rescued by Alyx promises that he and his race will take down the remaining power stations.
Eli contacts Alyx and warns her that the Vault does not contain a weapon; instead it was a prison built around an apartment complex in order to contain something that the Combine discovered. The Vault was then made to levitate in the deserted zone as an extreme containment measure. Alyx ventures on, reasoning that whatever is inside the Vault can help them fight the Combine. Upon getting closer to the Vault, Alyx overhears a scientist (Kim Dickens) implying to Combine superiors that the Vault contains a survivor of the Black Mesa incident. Assuming this survivor to be Gordon Freeman, Alyx aims to mount a rescue and successfully crashes the Vault to the ground.
Boarding the Vault, she finds the apartment complex which it was built around, suspended in a highly surreal state; bedrooms, kitchens and living rooms are superimposed on top of one another, and physical phenomena permeate the entire building, seemingly under the influence of space-time disturbance. Alyx navigates through the Vault's surreal contents and discovers an advanced prison cell in its center. She breaks it open, expecting to find Freeman. However, she instead releases the mysterious G-Man (Michael Shapiro), extracting himself and Alyx from the Vault.
As a reward, the G-Man offers his services to Alyx. She requests he remove the Combine from Earth, but the G-Man stresses that this request would contradict the interests of his "employers". He instead subjects Alyx to a future event, and offers her the chance to change the outcome of Eli's death at the hands of the Combine Advisor at the end of Half-Life 2: Episode Two. Alyx complies, killing the Advisor and saving her father. The G-Man informs Alyx that she has proved herself capable of replacing Freeman, whom the G-Man has grown dissatisfied with due to his unwillingness to carry out his given mission. The G-Man then traps Alyx in stasis and leaves.
In a post-credits scene set after the destruction of the Combine super-portal in Half-Life 2: Episode Two, Gordon regains consciousness in the Resistance's White Forest base. Eli is alive and the Advisor is dead, but Alyx is missing. Alyx's pet robot, Dog, arrives at the scene with Gordon's crowbar. Eli realizes what has happened to Alyx and declares his intention to kill the G-Man, and hands the crowbar to Gordon. The G-Man watches from a distance.
The previous Half-Life game, Episode Two, was released in 2007, ending on a cliffhanger. Episode Three was scheduled for 2008, but was delayed as its scope expanded. Valve eventually abandoned episodic development, finding it contrary to their growing ambition with new installments. After several failed attempts to develop further Half-Life projects, Valve decided to complete its new engine, Source 2, before beginning a new Half-Life game, as developing Half-Life 2 (2004) and the original Source engine simultaneously had created problems. Before the announcement of Alyx, three key Half-Life writers, Marc Laidlaw, Erik Wolpaw, and Chet Faliszek, left Valve; journalists took this, coupled with Valve's support for other franchises, as an indicator that new Half-Life games were no longer in development.
In 2015, Valve collaborated with the electronics company HTC to develop the HTC Vive, a virtual reality headset released in 2016. Valve experimented with VR games, and in 2016 released The Lab, a collection of VR mini-games. Valve recognized that many players wanted a more ambitious VR AAA game, and began exploring the development of a major game for the Vive. They developed several prototypes, with three further VR projects under development by 2017. They experimented with a VR game in their puzzle series Portal, but found that the portal systems were disorienting in VR, and settled on Half-Life. Designer Robin Walker said that Half-Life 3 had been a "terrifyingly daunting prospect", and the team saw VR as a way to return to the series.
Valve built prototypes using Half-Life 2 assets, and narrowed the gameplay systems down to those they felt best fit for VR. One of these prototypes became a minigame in The Lab. They found that the Half-Life systems were a "surprisingly natural fit" for VR, but that VR affected almost every aspect of the design; for example, shooting in VR, which requires the player to physically position their hand in space, is a different experience from aiming with traditional mouse and keyboard controls. According to Walker, "This all spirals out into every aspect of mechanics design, level design, pacing, and even things like frequency of ammo pickups and combat tuning." The crowbar, an iconic weapon from previous Half-Life games, was omitted as Valve could not make melee combat work in VR, and because players would accidentally catch it on objects in the game world as they moved, creating confusion. Additionally, players associated the crowbar with Gordon Freeman, the protagonist of previous games; Valve wanted to create a different identity for Alyx, portraying her as a "hacker and tinkerer".
When considering options for player movement, Valve drew inspiration from the VR game Budget Cuts, which used teleporting to move the player between locations. They found that while watching other players teleport looks jarring, players quickly became accustomed to it; according to Walker, “It recedes to the background of your mind, and you become much more focused on what you’re doing with it."
Half-Life: Alyx entered development around February 2016, and entered full production later in 2016. The team, comprising around 80 people, was the largest in Valve's history, and includes Campo Santo, a studio Valve acquired in 2018. Valve's Source 2 engine includes better support for VR and collaborative level editing, and Valve plans to release a new Hammer level editor for Source 2. Valve also plans to release a partial Source 2 software development kit (SDK) for the updated features at a later date, with the focus at launch on shipping and supporting Alyx.
The basic framework for the game's story always involved Alyx journeying through City 17 to release the G-Man, but the actual ending was left up to Pinkerton, Vanaman, and Wolpaw. The decision to end the game with a time-jump came about from having to solve two problems: how to give stakes to a prequel starring established characters whose fates were already known to the player; and what a character who is essentially a god (the G-Man) would give to his liberator (Alyx). The writers and later their fellow employees were initially reluctant to pursue this ending, as it more or less undid Episode Two's nearly 13-year old cliffhanger. But as they thought more about it, they found themselves intrigued by the questions it raised about the world of the game and how it pushed the entire Half-Life story forward.
Valve announced Half-Life: Alyx in November 2019. It was made free to owners of Valve Index headsets or controllers. To promote the game, all prior games in the Half-Life series could be played for free on Steam from January 2020 until its release on March 23, 2020. When asked about plans for future Half-Life games, designer David Speyrer said the team was willing but were waiting for the reaction to Alyx. According to Walker, "We absolutely see Half-Life: Alyx as our return to this world, not the end of it." Mod support tools for the Source 2 engine and Steam Workshop support for Half-Life: Alyx were released on May 15, 2020. Valve released a Linux version on May 15, 2020, along with Vulkan rendering support for both platforms.
Half-Life: Alyx received "universal acclaim", according to review aggregator Metacritic. Reviewers at publications such as VG247, Tom's Hardware, and Video Games Chronicle have said that the game is VR's "killer app". By April 2020, it was one of the top 20 PC games of all time based on the Metacritic aggregate score.
The announcement trailer was watched over 10 million times within the first 24 hours of its release. Though most fans expressed excitement, some were disappointed that the game is only available in VR, a small but growing market in 2019.
Before the game's release, Vic Hood of TechRadar said: "This certainly isn't the long-awaited Half-Life 3. However, it's nice to see Valve following through on a Half-Life project as the company has run hot and cold on whether we would ever see another entry in the series. But we forever live in hope for a Half-Life 3." Microsoft executive Phil Spencer said he played the game prior to its announcement, calling it "amazing". Kevin Webb of Business Insider wrote that Alyx could "spark fresh interest in an industry [VR] that has struggled to win over hardcore gamers". Andrew King of USGamer also suggested that Half-Life: Alyx would be the "make or break VR Jesus Moment" for the modding community, in whether the players would be interested and be capable of using the tools provided by Valve to producing new creations that took advantage of VR space, as modification within VR space has traditionally been difficult to work with prior to this point.
On its first day of release, Half-Life: Alyx had 43,000 concurrent players. According to Niko Partners analyst Daniel Ahmad, this was a successful launch by VR standards, matching Beat Saber's peak concurrent users. The peak number of viewers watching Alyx on Twitch was 300,000; according to Gamer Network writer Haydn Taylor, this demonstrated how the VR requirement had limited its potential player base.
The Valve Index headset, controllers, and base stations all sold out in the United States, Canada, and Europe within a week of the game's announcement. By mid-January 2020, they were sold out in all 31 regions the units were offered. According to Superdata, Valve sold 103,000 Index units in the fourth quarter of 2019 as a result of the Alyx announcements compared to the total 149,000 sold throughout 2019, and was the highest-selling VR headset for PCs during that quarter. Though Valve had expected to supply several Index pre-orders in time for the release of Alyx, the coronavirus outbreak in China limited their supply chain.