Franchise Festival #125: Half-Life / Portal

Welcome back to Franchise Festival, a column where we explore and discuss noteworthy video game series from the last four decades. Older entries can be found in the archive here.

This week we’ll be pulling all of the details about Half-Life and Portal through some manner of spatial anomaly. Cover art is from MobyGames. Please consider supporting that website, as its staff tirelessly catalogs key information and art assets for an often ephemeral medium.


Sierra Entertainment was founded in 1979 by Ken and Roberta Williams to create business software for early personal computers. The pair’s shared passion for text adventure games, however, soon inspired them to branch out into video game development. They pioneered the graphical adventure genre with Mystery House (1980) before rebranding as Sierra On-Line in 1982 and building their own extensive library of franchises, including King’s Quest (1980-2016), Space Quest (1986-1995), and Police Quest (1987-2008). After they went public in 1989 and were subsequently bought by CUC International, Sierra On-Line began to diversify their portfolio through the publication of games developed by small studios across North America. The timing couldn’t have been more serendipitous for Valve, which had been founded in Washington by former Microsoft employees Gabe Newell and Mike Harrington in Summer 1996.

Half-Life (1998)

Disappointed by the genre’s creative stagnation following 1993’s epochal Doom, Newell and Harrington decided to develop a first-person shooter that told a relatively complex science-fiction story without sacrificing punchy gameplay. Valve’s founders convinced former Microsoft coworker and then-id programmer Justin Abrash to let them use that studio’s Quake engine; Valve would modify this software into their own proprietary GoldSrc engine through the addition of skeletal animation and Direct3D graphics. The relationship with id proved fruitful beyond its technological elements, too, as it led them to hire Quake enthusiasts Steve Bond and John Guthrie as part of their 25-person team. Impressed by Valve’s thoughtful practicality, Sierra On-Line agreed to publishing responsibilities only 30 minutes into their initial meeting. Science fiction author Mark Laidlaw, who joined the team in Summer 1997, helped overhaul the game’s plot and integrate ally characters later that year. The revolutionary results spoke for themselves when Half-Life launched on PC in November 1998.

Circulating video from an early build of Half-Life, made available by Sierra as a bonus pack-in alongside Diablo: Hellfire (1997) feature unique non-player character (NPC) behavior and a different heads-up display (HUD) not present in the final version. Source: Half-Life Wiki

Inspired by Stephen King’s The Mist (1980), Half-Life‘s story depicts the catastrophic merger of alien world Xen with our own reality during an otherwise typical day at the United States government’s Black Mesa research facility. The player is introduced to this nondescript – if troublingly subterranean – setting through a lengthy tram ride experienced in real-time by theoretical physicist Gordon Freeman. After inadvertently kicking off a “resonance cascade” by performing an experiment guided by his superiors, Gordon must escape the facility while slaying legions of monsters and antagonistic Hazardous Environment Combat Unit (HECU) soldiers. He’s aided along the way by anonymous security guards, informed by Don Knotts’ portrayal of Deputy Barney Fife on the Andy Griffith Show, and a “sinister interdimensional bureaucrat” nicknamed G-Man by fans.

The G-Man can frequently be spotted behind doors or in otherwise inaccessible locations. Source: Half-Life Wiki

Though its basic gameplay matches the first-person shooter template established by Doom (1993) and Quake (1996), Half-Life adds a host of features that advanced the genre past unambitious contemporaries. Discrete levels are abandoned in favor of a sprawling facility separated only by the occasional loading screen and unobtrusive on-screen chapter titles. Bosses and combat arenas are eschewed in favor of organically placed opponents and obstacles which must be overcome by using environmental objects, like electricity and industrial equipment, rather than firepower alone. For better or worse, the final section of the game even takes Gordon to Xen and forces the player to adapt to a lower level of gravity while jumping between floating platforms.

Half-Life has more in common with science fiction than horror, but its roots in the gory action of Doom are still on full display. Source: MobyGames

Half-Life’s enemy roster replaces the monsters and demons of other 1990s first-person shooters with a variety of interesting alien life forms that enhance the game’s horror elements. Headcrabs are small, blind, quadrupedal critters that scurry along the floor and can parasitically control humans when affixed to their heads. Vortigaunts are humanoid cyclops that control electricity and attack from a distance. Barnacles, hidden away along the ceiling, can pull Gordon or other enemies up into their toothy mouths using a dangling tongue. The massive Gargantua are so heavily armored that their shells must be pierced through explosions or environmental damage before Gordon can gun them down. For your author, though, the Ichthyosaur is Half-Life’s most terrifying creature – this aquatic predator swims rapidly out of murky underwater areas to ambush and tear the player character apart in a matter of moments. Of course, these represent only a sample of the game’s multitudinous foes.

The platforming-heavy alien world of Xen is not among Half-Life‘s most popular sequences. Source: MobyGames

Half-Life was an overnight critical and commercial blockbuster, upending how first-person shooters were made and influencing a generation of story-driven titles in the genre. As Valve reflected on its success and explored how a sequel might iterate on such a strong foundation, it greenlit two expansion packs developed by Gearbox Software. The first of these, action-oriented Opposing Force (1999), depicts the events of the Black Mesa incident from the perspective of a HECU soldier sent in to contain the outbreak.

Players take on the roles of Black Mesa scientists Gina Cross and Colette Green in the PlayStation 2 port’s bonus mode, Half-Life: Decay. Though it’s intended for cooperative play, a single player can make their way through the whole adventure by switching between the two protagonists. Source: Zevik

Blue Shift, which puts the player in the shoes of Black Mesa security guard Barney Calhoun as he solves environmental puzzles and fights aliens in his own quest to escape the facility, was originally intended to be a bonus campaign included alongside a Dreamcast port of Half-Life but was published as a standalone PC release when that port was canceled due to “changing market conditions” in 2001. Thankfully, the source code of the Dreamcast version was later salvaged into a PlayStation 2 port that contains a unique two-player cooperative campaign titled Half-Life: Decay. Finally, a full remake in the Half-Life 2 engine titled Black Mesa was developed by a team of fans called Crowbar Collective and published as a full digital retail edition in 2020 following a lengthy early access period.

Counter-Strike popularized the team-based multiplayer military shooter genre through its ubiquity at LAN parties and internet cafes around the world. Source: MobyGames

Like other PC games of the early internet era, Half-Life inspired a wide variety of fan-made mods and multiplayer communities. The earliest of these, Team Fortress Classic (1999), was a class-based team deathmatch mode built on the structure of an unofficial Quake mod called Team Fortress (1996) by John Cook and Robin Walker after they were hired by Valve. The most influential multiplayer mode, however, was Counter-Strike; developed originally as a free mod by Half-Life fans Minh Le and Jess Cliffe and then published in a retail edition by Valve in 2000 after it acquired the intellectual property (IP) rights, this team-based online shooter was significant for its inclusion of selectable gear loadouts and asymmetric win conditions for the terrorist and counter-terrorist teams. Counter-Strike would be foundational in the burgeoning world of eSports, leading to a 2004 remake as well as sequels Counter-Strike: Condition Zero in 2004 and Counter-Strike: Global Offensive in 2012.

Half-Life 2 (2004)

As extensively documented in Prima Games’ Half-Life 2: Raising The Bar (2004), pre-production on Half-Life 2 began in early 1999. Veterans of Half-Life, alongside dozens of new employees, focused first on the integration of facial motion capture and real-time physics through the development of a new game engine known as Source. At the same time, Mark Laidlaw and his team sought to build out the series’ universe through an adventure that spanned multiple continents and an ice-breaker ship environment; many of these elements were slowly cut away in favor of a tight story set in Eastern Europe’s City 17. Gabe Newell then departed direct oversight of the project in 2001 to focus on the design of Steam, Valve’s own digital distribution platform, and production continued under his colleagues.

The translucent Hydra enemy – designed over the course of six months by programmer Ken Birdwell and prominently featured in footage from Half-Life 2‘s E3 2003 demo – was cut from the final version of the game because it was too irritating to fight in first-person. Source: Half-Life Wiki

Unfortunately, Half-Life 2 started to run into major hurdles around this time amid a lengthy legal battle with publisher Vivendi. After an early 2002 demo shown off to Newell disappointed the studio co-founder with overlong cutscenes and forestalled a planned announcement at that year’s Electronic Entertainment Expo (E3), the team successfully relaunched production with a September 2002 demo that highlighted interactive setpieces and enemy AI. Newell’s announcement of a September 30, 2003 release date at E3 2003 still proved premature, however, with staff unable to deliver a finished game following months of brutal work conditions. Thankfully, the outcry of frustrated fans didn’t convince Valve to compromise on quality and it proceeded on with production for another year. Half-Life 2 launched on PC in brick-and-mortar stores as well as the studio’s own Steam digital distribution service on November 16, 2004.

Omnipresent Combine soldiers and crumbling Eastern Bloc architecture convey City 17’s dystopian atmosphere. Source: MobyGames

The story begins with Gordan Freeman being awakened from stasis by the G-Man two decades after the Black Mesa incident and subsequent Seven Hour War that saw humans conquered by an alien empire known as the Combine. Gordon is saved by a charismatic young resistance fighter named Alyx Vance and discovers that the planet is now overseen by Wallace Breen, the mysterious administrator of Black Mesa who ended the Combine’s war of conquest by establishing a collaborative pact with them, from his headquarters in City 17’s towering Citadel. With the aid of resistance leader Eli Vance, teleportation specialist Judith Mossman, scientist Isaac Kleiner, former security guard Barney Calhoun, and oversized robot Dog, Gordon and Alyx make their way through the urban environment and its surrounding hinterlands as they work to free Earth from Dr. Breen’s authoritarian government.

Dog and Alyx are reliable allies, making Half-Life 2 less lonely than Gordon Freeman’s first adventure. Source: MobyGames

Gameplay represents a major step forward from most contemporary shooters. Enemy security forces make use of squad-based ambush tactics, while the presence of mechanical drones means that attacks can come from the air as well. Urban chokepoints give way to an eerie abandoned village, canals and beaches so vast that the player navigates them using vehicles, a dystopian prison, and finally the industrial core of the Combine’s post-human regime.

You can pick up objects with your hands, but the gravity gun makes it fun. Source: MobyGames

One of Haf-Life 2’s most enduring legacies is its integration of a consistent physics engine sourced from Ireland’s Havok studio. The ability to pick up and move environmental objects allows the player to solve puzzles and overcome obstacles in a seemingly improvisational fashion rather than by tripping invisible switches or eliminating a set number of enemies, as had been the case in most earlier shooters. This is dialed up to eleven when Freeman acquires the gravity gun, a weapon that can pull distant objects and then hurl them away at high speeds; the game’s climactic victory lap enhances this weapon still further with the ability to pull and toss enemies themselves.

Team Fortress 2 underwent a seven-year development period that saw its art design shift from a realistic military aesthetic to the exaggerated mid-20th Century animated style of the final product. Source: MobyGames

Valve had somehow caught lightning in a bottle for a second time. Half-Life 2’s pioneering use of in-engine storytelling, physics puzzles, realistic facial expressions, and thoughtful level design would influence an entire generation of shooters; it’s not exaggerating to observe that major milestone titles like BioShock (2007) and Call of Duty: Modern Warfare (2007) would not exist without Valve’s 2004 magnum opus. An Xbox port in 2005 disappointed with poor performance and the omission of the PC original’s multiplayer deathmatch mode, but the 2007 launch of the Orange Box on Xbox 360 redeemed the game’s console legacy. This collection included the base game, two episodic expansions that introduce new areas and a dangerous new pursuer enemy called the Hunter, a full sequel to Team Fortress that took advantage of the seventh console generation’s online multiplayer capabilities, and a spinoff called Portal. Though Valve’s uniquely flat corporate structure has ensured that Episode 3 remains unfinished nearly two decades hencein spite of its plot details finally being leaked in 2017 by writer Mark Laidlaw – this puzzle-based spinoff would provide the next major step forward for the Half-Life universe.

Portal (2007)

A group of seven students at Washington’s DigiPen Institute of Technology developed a senior project called Narbacular Drop in 2005. Produced by Kim Swift and directed by Jeep Barnett, this first-person demo sees players creatively placing two interconnected portals on surfaces to overcome six short levels filled with environmental obstacles. Valve’s Robin Walker noticed the project while attending the university’s annual career fair and invited the team in to show it off to his studio. Following the presentation, Gabe Newell hired all seven students on the spot to work their concept up into a full game.

Narbacular Drop looks very different from Portal, but the fundamental mechanics are already present. Source: Giant Bomb

The process took two years and involved no more than 12 people. While the core DigiPen team spent much of 2006 playtesting and refining puzzles using the Source Engine, Valve assigned a new writer named Eric Wolpaw to flesh out the story with a blend of dark humor and light horror. Narbacular Drop‘s simple narrative about a princess using magic to escape from imprisonment was dropped in favor of a science fiction setting as an expedient way to reuse Half-Life 2 art assets. Unsure of the best way to sell this relatively short game in an era that predated the indie revolution of the 2010s, Valve opted to package Portal as part of the Orange Box on PC, Xbox 360, and PlayStation 3 in 2007 alongside a standalone PC release. 

Portal opens in an isolated chamber deep within Aperture Science’s laboratory as protagonist Chell awakens from cryostasis and is led through a series of testing chambers by disembodied AI GLaDOS (voiced by Ellen McLain). Though these initially serve to tutorialize movement and use of the Portal Gun, a tool that allows the player to produce an entry portal and an exit portal on almost any flat surface, GLaDOS is revealed to have a sadistic personality and ulterior motives. Chell eventually discovers hidden areas behind the walls of the abandoned laboratory and learns the truth about what occurred there while she slept.

Chell exits her stasis chamber by using a portal. Source: MobyGames

Though the presentation and mechanics are borrowed from Half-Life 2, its gameplay is largely non-violent. Each of the game’s 19 core testing chambers presents the player with a locked door that they must open and navigate to through a combination of first-person platforming and thoughtful placement of reusable portals. Stationary enemy drones, which will annihilate Chell if she enters their line of fire, can be knocked over or picked up and moved if approached from behind. One chamber memorably requires Chell to escort a “companion cube” and then heartlessly incinerate it before moving on. Though a variety of less successful final confrontations with GLaDOS were prototyped, including a chase sequence and a traditional combat-oriented boss battle, the developers wisely settled on a timed puzzle that builds on the environmental manipulation of earlier chambers.

The testing chambers present a positive first impression, but the hidden areas get very troubling very fast. Source: MobyGames

Portal was an overnight success, resulting in the publication of a standalone version featuring additional puzzles on the Xbox Arcade digital marketplace as Portal: Still Alive in 2008 and a Nintendo Switch port in 2022. Its humor and eerie setting led to a proliferation of memes during the early days of social media – who can forget “the cake is a lie”? – while its tightly designed puzzles ensured that it consistently attracted new fans over the following years. With a genuine cultural phenomenon on their hands, even Valve’s reticence to directly iterate on past successes couldn’t stand in the way of a sequel.

Portal 2 (2011)

Valve staff claimed at the 2012 Game Developers Conference that the primary reason for Portal 2’s existence was the sheer number of staff who were disappointed they’d missed the opportunity to work on the preceding title. The project began in 2007 under the same core team that had developed Portal, but rapidly expanded to a include 40 individuals. National Lampoon’s Jay Pinkerton and Left 4 Dead’s Chet Faliszek were brought onto the project as writers to help Eric Wolpaw expand on the universe he’d created. 

F-Stop/Aperture Camera was the subject of speculation for years, but Valve finally allowed indie studio LunchHouse to produce a video showing off the implementation of its source code in 2020. Source: BoxandRocks

Early prototypes that omitted Chell, GLaDOS and portals in favor of a 1950s setting and an ability to duplicate objects through photography (known alternately as Aperture Camera and F-Stop) were abandoned in favor of a direct sequel after playetesters expressed frustration at the lack of mechanical continuity. As they had done with the Narbacular Drop team several years earlier, Valve hired a group of DigiPen students who’d demonstrated a paint-oriented prototype called Tag: The Power of Paint at the 2009 Independent Games Festival and asked them to adapt their work as part of Portal 2. The final game launched as a standalone release on the Xbox 360, PlayStation 3, and PC worldwide in April 2011.

Time hasn’t been kind to the testing chambers of Aperture Science. Source: MobyGames

Players once more take on the role of Chell as she escapes from Aperture Science in the distant future, having been put into stasis at the end of the preceding adventure. The facility is now falling apart in spite of GLaDOS’ best efforts to rebuild it, however, and the player must navigate returning test chambers as well as long-abandoned areas from Aperture’s experimental early work in the mid-20th Century. Along the way, Chell is accompanied for a time by a humorous personality core robot named Wheatley (voiced by Stephen Merchant) and learns about brash company founder Cave Johnson (voiced by J.K. Simmons). GLaDOS’ disturbing history is revealed through audio logs discovered within Aperture’s deepest layers.

Hopelessly dumb personality core Wheatley guides Chell through transportation tubes during Portal 2‘s early hours. Source: MobyGames

While the development team opted not to abandon the mechanical structure they’d established in Portal, the integration of Tag staff and other thoughtful Valve designers allow for a wider range of puzzles than were present in the previous title. Tractor beams and lasers must now be routed through portals within stages featuring more natural, organic level design. Gels that alter the way that Chell moves, sliding her along the floor or granting higher jump abilities, are similarly integral to overcoming environmental obstacles.

Blue gel can launch Chell or puzzle objects up to high platforms. Source: MobyGames

Portal 2’s most surprising new element is a cooperative mode featuring autonomous testing robots. As ATLAS and P-Body, two players must communicate with one another to solve complex asymmetric puzzles requiring the use of four portals in splitscreen or online multiplayer. The story sees GLaDOS guiding the pair to a chamber filled with new human test subjects and realizing that inorganic beings’ inability to experience pain makes her observation of their travails less meaningful. A downloadable content package titled Peer Review expanded this plot further when it launched in October 2011, moving the story a week into the future and focusing on ATLAS and P-body’s efforts to uncover an unlikely saboteur within Aperture Science’s walls.

Unlike Chell, ATLAS and P-body must carefully coordinate their actions to overcome GLaDOS’ trials. Source: TeraBrite Games

As with Half-Life 2 before it, Portal 2 managed to improve on an iconic video game experience. Fears that the svelt perfection of Portal couldn’t be duplicated in a longer adventure were accurate, but fans were overjoyed to find that a messy evolution on Wolpaw’s story and the wider team’s portal mechanics could be more satisfying than elegance. The game has endured as a towering work of puzzle design for the past decade – with its level editor even being used in schools to teach spatial thinking and evaluate critical analysis – and was finally ported to modern hardware with improved performance as part of the Switch’s Portal Companion Collection in June 2022.


Half-Life inspired a wide variety of mods and spinoffs. The best of the former are covered thoroughly by Noah Caldwell-Gervais’ video essay “Custom Game: Revisiting the Single-Player Mods of Half-Life 1,” while the latter include the two standalone single-player campaigns and two multiplayer titles described above. Half-Life 2’s engine was then used to power sequels to its predecessor’s multiplayer spinoffs – Team Fortress 2 (2007), Counter-Strike: Source (2004), Counter-Strike Online (2008), Counter-Strike: Global Offensive (2012), and the Asia-exclusive Counter-Strike: Online 2 (2013) – as well as Portal.

In this scene from Half-Life: Alyx, you can see the gravity glove on Alyx’s left hand and a diagetic indicator of the remaining bullets in Alyx’s handgun. Source: Steam

The only spinoff directly connected to Half-Life 2’s single-player campaign is Half-Life: Alyx, a first-person shooter developed by Valve and published for its Steam Index virtual reality (VR) headset in 2020. Players finally get to control Alyx Vance in an adventure set five years before the events of Half-Life 2. Like its source material, the gameplay combines tense shootouts and puzzles that hinge on the manipulation of objects using gravity gloves.

In this (somewhat silly) promotional screenshot of The Lab, an HTC Vive user fires arrows at a gate in virtual reality. Source: Steam

Even leaving aside multimedia tie-ins like Cryptozoic’s board game “Portal: An Uncooperative Cake Acquisition Game” and the Portal 2: Lab Rat comic, Portal produced nearly as many spinoffs as its parent series. The first of these – The Lab – was developed internally by Valve and published in 2016 as a free piece of software included with the HTC Vive VR headset. It serves to show off the features of that hardware through a variety of minigames and interactive spaces set in the Aperture Science laboratory.

Though it’ i’s presented in 2D, Bridge Constructor Portal wouldn’t be possible without the complex physics engines popularized by Half-Life 2 over a decade earlier. Source: MobyGames

The franchise’s next spinoff was developed by ClockStone and published on PC and mobile devices in 2017 by Headup Games with Valve’s blessing. Bridge Constructor Portal – the fifth entry in ClockStone’s Bridge Constructor franchise – sees players using portals and bridge struts to convey trucks from a starting destination to a goal within 2.5D Aperture Science levels. Ellen McLain reprises her role as GLaDOS, supervising the player’s actions and offering a multitude of sardonic quips. Home console version launched on the PlayStation 4, Xbox One, and Switch in 2018.

Playing rock-paper-scissors against a personality core in Aperture Hand Lab. Source: Pure Gameplay

Valve next returned to VR with 2019’s Aperture Hand Lab, developed for the Steam Index in collaboration with Cloudhead Games. As with The Lab before it, this game is more or less a tech demo designed to show off unique hardware features. Since the Steam Index is noteworthy for its finger and hand tracking capabilities, Aperture Hand Lab emphasizes the use of fine motor functions to interact with environmental puzzles.

As Aperture Desk Job demonstrates, you can cause a lot of mayhem from the comfort of a desk. Source: Steam

Portal’s final spinoff at the time of writing, Aperture Desk Job, was developed by Valve and released for free alongside its handheld Steam Deck console in 2022. With the aid of a personality core named Grady, the player completes tasks at Aperture Science using unique Steam Deck hardware elements like the touchscreen and gyroscopic aiming from a first-person perspective. Despite its role as promotional material, the game can be downloaded and played using a controller on traditional PC setups with a bit of ingenuity.


Given Valve’s roots in hardware and operating system developer Microsoft, video game enthusiasts could be forgiven for having assumed that the studio would amount to little at the time of its founding in 1996. Contrary to expectations, however, studio co-founder Gabe Newell and his staff soon launched one of the most influential first-person shooters of the decade. Half-Life inspired numerous mods and spinoffs before finally producing a direct sequel in 2004. 

Half-Life 2 would be just as significant a milestone as its predecessor, giving rise to the ubiquity of physics engines in nearly every video game genre over the following decade. Even as the studio pivoted to distribution through its Steam platform, Valve found time to hire new staff and introduce one of the new century’s most beloved properties in 2007. Portal was popularized through a cacophony of memes and winking acknowledgements during the early days of Web 2.0, and its sequel somehow built upon a foundation that seemed impossible to surpass. Even spinoffs developed primarily as tech demos reliably reviewed well. Regardless of whether Valve ever delivers the long-requested Half-Life 3 or Portal 3, it will retain its reputation as a studio that’s never fallen short of excellence.

What do you think about Half-Life and Portal? Which is your favorite series entry? How about your favorite character, alien, and/or GLaDOS one-liner? Xen: like it or love it? Let’s discuss in the comments below.

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