There is a peculiar irony to the impression people have of gaming. When “videogames” are lazily portrayed in the wider world, they inevitably show a soldier being shot through a gun scope. Hell, even within the highest enclave walls, people are wont to dismiss the poor taste of others by snarking, “They’d probably like it if it had a gun floating at the bottom of the screen.” The first-person shooter is the most emblematic genre of gaming, and yet it’s now the most under-served, under-developed, and rarest of mainstream releases. There are barely any new non-indie FPS games. And it’s all Half-Life’s fault.

In the early-to-mid 90s, the FPS became a dominant genre on PC. The phenomenal success of Doom and Quake saw waves of similar titles filling shop shelves, the games seen as the most accessible, the most immediately fun, and in turn, the most despised for being so prolific. The relative simplicity of building corridors from pre-established engines meant it was easier for bad as well as good games to get developed, and critical mass always leads to mass criticism. And then in 1998, along came Half-Life.

Half-Life wasn’t the first game to set an FPS in recognisable environments. Duke Nukem 3D likely holds that crown. But when those early screenshots appeared in PC Gamer, and we saw offices, laboratories, places of work, rather than spaceships and brown tunnels, it was revelatory. But we still didn’t know about the set-pieces. The events that would occur around us, magically happening just as we walked into the room. Rather than simply spawning a big monster when we passed through a door, Half-Life started telling us stories when we showed up.

Rather peculiarly, in the six years that passed between then and Half-Life 2, very few other developers had the ambition to try this. While there were many incredible FPS games contemporary to Half-Life – AvP, Thief, Call Of Duty, Jedi Knight, Medal Of Honor, Quake 3… – they all stuck to traditional methods of storytelling, if they had stories at all. Cutscenes, text on screen, barked words in your head, rather than letting the place you were in be the story you were told.

Come Half-Life 2, Valve returned, at last, showing everyone what it was they hadn’t been doing. While HL2 does have cutscenes of a sort, they remain interactive, offering you limited movement as the conversations are playing out. But more often, it is a game that unfolds in sensational set-pieces occurring around you. And it is this that has killed the FPS today.

While Half-Life’s innovations were tiresomely unexplored by so many in its wake, Half-Life 2’s world-conquering attention made it unavoidable. Where HL1 was about the little details, subtlety, HL2 was about enormous events, explosive action happening spectacularly about you. It set a new standard for FPS gaming. A standard that, it turns out, costs hundreds of millions of dollars to make.

The lines, from HL2’s spectacle to the non-interactive set-pieces that dominate the very few shooters that now get made, are fairly straight ones. Call Of Duty’s annual attempt to have a slightly bigger building fall over when you walk into a scene is a direct extrapolation of everything Half-Life 2 began, as publishers, if not also players, demanded extravaganza.

And doing that is awfully expensive. If your game is comprised of the narrowest corridors, then you have to make an awful lot of them to see it last the necessary six hours of the modern shooter (compared to the 15 of the 90s era). With no fields to criss-cross, no large zones to explore, there’s no room for letting the player re-enter the same area again. This inefficiency is stunningly expensive to do. Add to this the cost of developing bespoke scripted sequences at every point, rather than allowing emergent content to be generated by the player’s interaction with your systems, and you’ve got to employ an army of artists, coders and designers, for a very long time. Where the survival genre saw the advantage of creating a large space and letting the player find interesting ways to die, the FPS has become something that requires you to stay alive, facing the right direction, on an inexorable moving walkway.

In 2005, Call Of Duty 2 cost $14.5 million. By 2009, Call Of Duty: Modern Warfare 2 cost Activision an extraordinary $200 million. $50m to make the game, and seemingly $150m to market and distribute. The consequence of spectacle is a financial one, and it’s priced almost everyone else out of the market.

Look at the current competition. Far Cry, Titanfall, Borderlands, and Battlefield. With the outlier of Wolfenstein, that’s the roster of 2014/15’s FPS releases. Exceptionally expensive games made by massive teams, with monolithic marketing campaigns. All within the budgets of the companies, and all making a profitable return. Good business no doubt, and in some cases, good games too. Massive budgets and development teams are of course capable of creating great shooters. But when that becomes the expectation of the player, it does rather raise the entry fee beyond the majority of developers.

And that has seen a phenomenal fall in FPS releases. According to Wikipedia’s listing, 1994-95 saw 64 FPS games come out. In 2014-15, so far, it’s been ten. It’ll maybe reach 15 by the end of the year.

And this all began with Valve and Half-Life.

It would be madness to affix any suggestion that Valve had this in mind. They set out to make the best game they could, and in doing so, made the best FPS game ever. If anything, it’s a rather woeful misunderstanding of what made its single-player game so extraordinary that has resulted in the near-termination of the genre. What Half-Life understood was that as impressive as the world around the player might be, their autonomy in that world remained the most important aspect. Yes, it’s a corridor, and indeed, those events will play out so long as the player continues to press W. But in Half-Life, the player chose to press it. If something big happened on the left, the game gave you big hints to look over there, but let you look over there.

As it turns out, Valve were doing something incredibly difficult, but making it look easy. Something it seems so many big publishers missed when beginning this spiral down the money well.

What we see now are shooters that have spent so much money making that building fall over that they simply cannot stand the idea that the player might not look at it, and as such control is endlessly wrested away to force viewing. In fact, the player can’t even be trusted with that W key any more, required to follow other characters, dragged against their will in the prescribed direction, distant attractions prohibited by “leaving the mission area” demands.

This combination of expense, and a lack of understanding of why those decades-old games worked so incredibly well, has seen the FPS dwindle away, despite the peculiar belief that it represents all of gaming.

As Half-Life’s ethos sees the bitter results of development-ad-absurdum, the shooter has lost its spirit, its vitality, and most of all, its scrappy, imagination-led development. The FPS is almost dead, and Half-Life is the killer.

So THANKS, Half-Life.