Note: The following article contains major spoilers for Half-Life, Half-Life: Opposing Force, and Half-Life: Blue Shift.

The Gearbox Software of today is barely recognisable as the fresh-faced Texas developer that launched in 1999. The studio did its stint in the WWII shooter genre with Brothers in Arms and is best known for its firepower delivery chute, Borderlands. Yet, for its first six years in the industry, Gearbox mostly supported existing series. It's honest but undervalued work that's kept many a company afloat over the years. Like Valve Corporation, Gearbox was founded by a rag-tag team of expats from another workshop. Where Gabe Newell and Mike Harrington were straight outta Microsoft, the Gearbox founders hadcuttheirteeth at 3D Realms and Bethesda. This was a young, independent studio with roots in both FPS engineering and narrative dreamweaving. It had plenty in common with Valve, and so it was a logical choice to write the Half-Life expansion packs.

Released in '99, Half-Life: Opposing Force was the first of these two supplements. In it, we play Corporal Adrian Shepard, one of the US Marines sent to Swiss Cheese the resident researchers and alien invaders at the Black Mesa Facility. The DLCs of the last five to ten years have rarely changed up the protagonists of their stories. Plenty of modern games are based around one character that you continuously upgrade over time. So, if the developer has you switch perspective, you lose all your pretty trinkets. Half-Life is more about the journey rather than a growing protagonist or the spoils of war. This allows it to migrate you to a new avatar without it feeling like it's robbing you of your riches. Although, who your protagonist is still counts for a lot.

Corporal Punishment

While Gordon Freeman was thinly drawn, he was fun to roleplay because he was perhaps the only scientist in action games doing scientist stuff. Gearbox's invitation to be a soldier in an action game is one that could have been sent to you by thousands of other interested parties. But this expansion is remembered for subverting through other means, for flipping the script of the heroic empowerment fantasy and letting you embody the villain. It shouldn't be. Officially, you play a Marine sent to perpetrate war crimes, but when it comes to the grisly business of killing civilians, Opposing Force gets squeamish.

As you arrive in a Black Mesa employee's workspace, they have to know they're face-to-face with the reaper, but there's never a flicker of discomfort from them. During the first act, a Isaac Kleiner-type guy lets you know he's aware of rumours soldiers are rubbing out scientists, and he still treats you like you're there to fix the photocopier. And never are you directly ordered to end someone's life, half the reason the government sent you to this boiler room in the first place. There are more opportunities to kill physicists in the base Half-Life, where you are a colleague to the researchers, than in Opposing Force, where you are their state-assigned executioner.

It's not that there's an article of storytelling that rules Shepard has to obey his superiors when they say he must murder. But if he's disobeying them and the writers don't state firmly that he made that choice, they're not communicating the plot to their audience. The game also casts you in a benevolent light through the gel of moral relativism. You might be a bad guy, but the real bad guy is the "Black Ops" who are at the labs to carry out an even more dire duty. It's hollow because, for most of the expansion, it's unclear what separates you from the Black Ops besides the colour of your fatigues.

Mission Critical

An uncomfortable question arises for Opposing Force, one that it's stimyed when trying to answer: If Shepard is not a harbinger of death, then who is he to Black Mesa? Gordon Freeman's goals were to escape his bunker, pull the breaker on Xen's organising intelligence, and close the portal. Barney Calhoun is the protagonist of Blue Shift, the second Half-Life expansion. He is entrusted with protecting the facility's scientists and, later, smuggling a small group of them to safety. What's Shepard doing? Hanging out? He can smoke some aliens while he's in town, but we know he ultimately can't halt the Nihilanth's ingress because Gordon's already got that covered.

In Opposing Force's eleventh level, "The Package", we learn from a cowering researcher that the Black Ops are in the facility to arm a plutonium warhead. Again, Half-Life puts the topic of nuclear disaster front and centre. After receiving this disturbing news, we walk to the other side of the car park, find the bomb in the back of a flatbed, and disarm it with a single button press. The time between alarm and all-clear and the ease with which we disable a nuclear payload means it could be one of the jokes from Jazzpunk. "Press E to defuse nuke" is a primordial "Sit down to hear intense news". But Opposing Force isn't laughing, and to the extent the defusing does give Shepard some status in the mythology of Black Mesa, it comes in Chapter 11 of 12. It won't make any difference in the grand scheme of things anyway. The facility still explodes.

I'm not even sure what Opposing Force's Black Mesa is to Black Mesa. In Gordon's Half-Life, you can invest in the research facility as a location because each level is one of the departments that operate the place, and there's plenty of evidence that those areas act towards their stated aims. Opposing Force is an industrial madlib. All the right props are there: fans, furnaces, pools of radioactive goop, but it's always a flip of the coin whether the expansion encases them in a cohesive pipeline. Therefore, it becomes difficult to believe that scientific illumination is happening here.

In the environmental and interaction design, Gearbox is trying to put you in the headspace of a military officer. Freeman was posted in the labs, where a scientist would be of the most use, and with his PhD in physics, he knows how to find scientifically-backed solutions to problems like turning on reactors and launching rockets. But control panels and sensitive instruments aren't of much use to a soldier. Shepard's world is one of gritty on-the-ground militarism. He's crawling the tunnels, skulking in the warehouses, and crouch-jumping like he's still at boot camp. He's more likely to use his agility, brute force, and the chain of command to solve a problem rather than academic knowledge.

The level Crush Depth has this wonderful communicator of who Shepard is: there's a malfunctioning x-ray machine we must pass through, and it's lit up with arcing electrical charges. Here, Freeman would reroute the power or find the off switch, but as Shepard, we unblock the route by blowing up the electrical relay with a gun. There's another such moment in Friendly Fire: You need to give your squad access to an indoor car park, but the buttons to open the shutters are damaged. Undeterred, you detonate some mines to destroy the debris blocking a door and let your team use the side entrance.

HECU

The X-ray machine and mines aren't the only setpieces with which the developers have fun. There's the board room in Friendly Fire where a Vortigaunt bursts through a projector screen as if it were a movie monster come to life. There is the return to the tram ride from the original game in "We Are Pulling Out". This time, you find incendiarised, stationary cars, letting you know that you're joining the party long after the fire was started. And there's the teleporting alien encounter in Vicarious Reality. Vicarious Reality is effectively an alien zoo, and in one enclosure, you see a trail of dead bodies and an open door. The subtext is clear: the alien killed its captors and fled. You run to the end of the corridor overlooking the enclosure only to find the exit is locked. So, you turn around and make your way back, but aliens zap in in front of you, breaking the glass of the exhibit. When you jump through the hole in the glass, it turns out that despite the unlocked gate, the Voltigore is still home, and it materialises in front of you. Here, environmental storytelling is a form of misdirection.

But while those filmic sequences have a certain wow factor, being a non-scientist in this scientific facility, we cannot have a conversation with it. Spaces in Opposing Force also generally feel barer than in the erstwhile Half-Life. Then, there are the localised design flubs. Pit Worm's Nest is a store-brand version of Half-Life's sixth section, Blast Pit. Without even leaving one expansion between the original operation and itself, Opposing Force exhumes the concept of a gaping hole with a leviathan rising out of it. In Pit Worm's Nest, as in Blast Pit, that abomination slices at you with razor-sharp scythes. It's not just that centrepiece that's bootlegged; it's also the mission flow as you must, again, flip switches in two tangential departments and then return to the main chamber to vanquish the monster. If that's not derivative enough, Opposing Force's stage also has Blast Pit's airlocks. I don't know why we're going back to the well already or why we'd want to do it with suffocatingly thin corridors or an excess of acid-spitting enemies. I'm tempted to ask if a single expansion pack needs three different aliens with corrosive projectiles.

If it's a glut of the same encounters you want, there's also Chapter 10, Foxtrot Uniform. Foxtrot Uniform is proud of its waffle of concrete tubes infested with Voltigores. Voltigores are elephant-sized and can shoot lightning orbs and charge like bulls. This combination of enemy and environment means you can be walking into a black veil only to have a ball of energy or a fleshy beast come flying out of it and annihilate you. This is one of many locales in which you must activate your night vision goggles, Opposing Force's equivalent of the flashlight. Filling your screen with console green, the goggles are visually offensive every time, and even with them, the draw distance in the tunnels is myopic. When you can get a bead on the Voltigores, you're given little elbow room to avoid their charges or the explosions they let off when they die.

Nothing made me close the original Half-Life as often as getting killed by blind fire, and Opposing Force can't get enough of it. Take "The Package", where it's par for the course to pop your head out of a doorway and spend a second locating your enemy. During that second, the enemy won't hesitate to attack you before you can determine what angle they're firing from. It's a tendency of shooters I'm more than happy to leave in the 90s. Towards the end of Opposing Force, you average an extreme number of deaths per meter and encounter surplus spawns of the same creatures, trapping you in an extradimensional Groundhog Day.

I do have to applaud the design of the Pit Drones, which dash towards us like they have a nitrous tank strapped to them. Every time, it makes me freak out, but is also a little amusing. They're like a Headcrab capable of a continuous lunge but which cannot leave the ground. The Shock Troopers are interesting as a draft for the Half-Life 2 Headcrab Zombie, dispensing a flesh-eating leech when they die. It wasn't until playing Opposing Force that I realised that it was Gearbox rather than Valve that came up with this concept of the after-enemy. But the leeches are slow and can only survive for a few seconds outside of their host, whereas the Headcrabs are jumpy little mites that it's up to us to exterminate. So, where Valve's residual enemies are a call to action, Gearbox's encourage waiting around a corner and doing nothing until your pursuer dies of exposure. Sometimes, there are so few scientists and the alien population in Opposing Force is so distinct from that in the base game that it's hard to believe it takes place in the same setting.

I also can't forgive how unceremonious the fight with the game's final boss, the "Gene Worm", is. It employs a standard cycle in which you have to shoot two weak points on the antagonist, exposing a third weak point, which is what we really want to eviscerate. But that third sweet spot is a pink portal. The defining feature of a portal is that matter passes through it rather than colliding with it, and when you shoot at the glow, you don't dislodge any particle effects or pained roars from the Worm to tell you you're making a dent. And, of course, this big fella has vats of health. Therefore, the feedback suggests that rather than the centre mass being the boss's Achilles heel, shooting it doesn't do any damage at all.

Learning two of the grossest habits from Half-Life's Nihilanth stage, Opposing Force's Worlds Collide is also waiting-room quiet and jerky in its pacing. When you incur an injury, which is easily done, you need to exit the room, shimmy up a rope, and then stay stationary in the healing pool to restore your health at a rate of about 1 point per second. It's such an insult to the player's time. It's alsobeenunacceptablylikely that the player would slay the Gene Worm only to have a glitch prevent the ending from triggering. And not to get personal, but Gene Worm, if you're reading this, your house looks like shit. The room is dilapidated and mismatched, dirty but a mundane dirty. It has about seven different materials patched over each other and a rusting yellow metal facing you every time you reenter. You're gunning down Cthulhu in an underloved shed.

It's not the only environment I have a problem with. In Chapter 4, Missing in Action, you appear to be trapped at the bottom of an elevator shaft but can find an escape by climbing a grate like a ladder. It's a stupid puzzle because there's nowhere else in the game that you can climb a hatch; it's been drummed into you by this point that they're only ever decoration or destructibles, and yet, here, one is your ticket out of the pit.

There's also an area I have to mention in Friendly Fire, not because it has a strong bearing on the quality of the levels as a whole, but because it boasts the most bizarre architecture I've seen in a game. You enter what looks like an office reception area with a skylight in the ceiling, but if you break the skylight, there's only rock above it. Make your way across the lobby, and you'll discover another pile of rock directly outside with a ~100m human-made tunnel through it. So, you've got a skylight built somewhere it doesn't get any light, an office that opens directly onto a mountain gorge, and the architects have bothered to build a tunnel through a hill when there's a short path around it anyway. You don't have to think about the practicality of the canyon lobby for it to bother you. Because it's not structured like any space we'd visit in the real world, it feels wrong to be there in the virtual one.

Bug Out

While we can single out dodgy settings and encounters, you have to stand back to see the contusions on the weapon set. There isn't one implement I would grade an F. The worst I could say is that the Wrench moves like I'm swinging it underwater, but the option to wind it up for heavier blows gives you a depth with your melee implement that shooters usually reserve for a ranged weapon. The game also gets in the military spirit with tools that pump up the damage, like the Combat Knife, which delivers a flurry of strikes with a short depression of the left click, or the formidable Desert Eagle, which you can shoot either by eye-balling your target or with a laser sight.

I have a soft spot for the Spore Launcher, a living gun that eats ammo and spits bullets. But you have sixteen weapons, some of them with alternate fires, in a campaign that players beat in an average of five and a half hours. This loadout feels like the gestation of Borderland's smorgasbord of loot, but in Opposing Force, unlike in Borderlands, there's not enough time to put all of your guns through their paces. Conceivably, that top-heavy fraction could be a motive to replay Opposing Force, but the shortcomings I've mentioned here make slamming my hand in the oven door sound more tempting than hitting "New Game".

Field Exercise

A lot of the original mechanics in this Half-Life don't get more than fifteen minutes of fame. Although, it feels less that Gearbox is leaving potential on the table and more that the mechanics were never fostered past a tutorial form. There are now ropes that you can climb, like the one in the Gene Worm battle. They split up how you course through Black Mesa's veins, but the 1999 physics engine can't simulate the sway of a rope, so they're more like sticks. Big sticks for you. If you see a radio in the environment, you can use it to call for backup, or if you run up against a sealed door, you can lead an engineer towards it and have them divorce it from its hinges. It's not nothing; you're acting the part of a soldier, but it does feel like acting. It's inauthentic. You don't have options for how you send out a distress call, and it's not a challenge to operate the transmitter, so this radio lacks the complexity of the real-world devices. And always assigning the welding man to the weldable doors means you don't have to mull over the delegation of duties that a military authority would.

Opposing Force also undoes some of Half-Life's commendable work in convincing you that its soldiers are intelligent. They never follow close enough for me to be sure they're at my back, and I need to keep checking behind me when I have them in tow because they can easily bump into a wall and stop moving. Even a Roomba would change directions. And they don't shut up, belching unprompted monologues that sometimes don't make sense given the context. I've seen them kill a human and brag about how much they love murdering aliens. Because they keep pulling from their ten awesome action phrases, they run out of script and start cycling back through it fast.

The most enhancing new mechanic is one of the most discrete. It's the medic. Both Freeman and Shepard's Black Mesas contain first aid stations. The stations have a limited amount of health that the player can transfer to themselves, point by point. Opposing Force's medics are essentially first aid stations that follow you around. A portable health battery is a generous leg up to give a player, but the boon they provide is offset by the intimidating attack values of endgame enemies. Because the first aid stations are fixed, you were sometimes encouraged to backtrack to them to make sure you were fighting fit for the battles ahead. The medic, however, can always march shoulder-to-shoulder with you, eliminating the need for any boring return journeys. They are the fellow troops that I felt most reliant on throughout the Black Mesa campaign.

Fissile, Futile

Despite the occasional company of engineers or medics, a lot of Opposing Force is about a man who comes from a tight-knit squad being separated from his fellow servicemen and forced to fight alone. In "We Are Pulling Out", you can do nothing but watch as your fellow marines evac without you. At the end of Worlds Collide, Shepard is completely disentangled from reality. Opposing Force has easily the darkest terminus of any Half-Life game. Shepard disarmed the government's bomb, but it went off anyway. If you linger by one particular window in "The Package", you can see the G-Man rearming the device after we defused it. Adrian becomes trapped in a catch-22. The man with the briefcase finds him too fascinating to let die but too dangerous to roam free. The corporal is stranded in a cosmic limbo pending "further evaluation". A cliffhanger is only as gratifying as your follow-up on it, but Half-Life never revives Shepard from his stasis. Gearbox couldn't work out what to do with him, and to this day, Valve hasn't either.

Armed

Half-Life's first expansion is at the top of its game when it comes to transforming the platform beneath it. It was a landmark release because it didn't just add a couple of guns or enemies for a new campaign. It's bursting at the seams with weapons, and it feels like an alternate universe version of Half-Life, which might be the worst thing for it. Yes, Opposing Force realises you as an outsider in Black Mesa, but in doing so, it disconnects you from its environment. It has more guns than you'd ever expect from a six-hour campaign, but another way of saying that is that it's cluttered. In 1999, that opulence of mechanics was welcome, but in an era where every AAA game is stuffed to the gills with "content", there's not much novelty to it, and the expansion languishes in disorganisation. Thanks for reading.