The Stephenson voice is not quite the Stephenson voice. Not the Stephenson voice from books like Snow Crash or Cryptonomicon, anyway - and perhaps I was stupid to think it would be.

In the novels, I love Stephenson's glibness, his knockabout nature, his choppiness when dealing with the intricate ideas he bases his narratives around. He's breezy in the face of vast forces, and the worlds he creates stutter outwards in a weirdly panoramic sort of present tense.

There's some Gibson in there, but there's also a touch of Pynchon, too. And there's quite a bit that's just Stephenson, of course: happy with mineral complexity when others are menaced by it, able to see the chaos of difficult systems raging behind even simple things - and to spot the order lurking beyond the chaos, too.

In person - over a Skype video call, at least - he's measured and succinct, however, and he has a surprisingly gentle tone. There's humour, but it's deadpan, accompanied by the odd shy chuckle. There's complexity - there's always complexity with Stephenson - but it's engineered, arranged, broken down and presented in tidy clauses.

Stephenson writes about games and technology as often as he writes about swords.

If you expected Stephenson to come across as a sweaty-eyeballed stream-of-consciousness data-jockey type, then, you're in for a shock: he sounds more like the sort of guy you might find in a Midwest feed store, offering an unusually engaging treatise on the best way to take a combine harvester apart.

Quirky, though? You bet. With his shaven head, dark eyes, and olde worlde goatee, Stephenson certainly looks every inch the warrior monk of speculative fiction, and he chats to me while working out on a treadmill, endlessly marching forwards, never getting any closer.

It feels a bit like a metaphor, really: much effort, slow progress. That's not just a metaphor for what it's like to be interviewed by a sub-literate like me, either. After all, a few weeks back, Stephenson launched a video game Kickstarter, and the reason he's talking to Eurogamer is that, with 14 days left at the time of our conversation, he's still over $200,000 shy of his $500,000 target. (As this is published, he's got four days left, and just under $80,000 to go.)

Hold on - Neal Stephenson's launched a video game Kickstarter?

He has, and it's called Clang: a simple name for a simple premise - in concept, if not execution, anyway. Clang's a multiplayer arena-based fighting game that aims to introduce players to the thrills and depth of the ancient European sword arts. It will use motion controllers (at the moment, the team's keen on the low-latency Razer Hydra) to recreate all those swings and lunges, and there will be plenty of scope for user-generated content.

This is a fiercely challenging prospect for a design team at the best of times, of course. The fact that it's also the first video game product from the Subutai Corporation, Stephenson's transmedia collective, suggests that the novelist and his friends like their work, um, cut out for them. It's hard not to get drawn into the idea, though. The thought of a writer who's circled games for so long finally touching down with his own project should be ludicrously exciting to nerds everywhere, and there's a simple romantic glamour to Clang, too, summed up in a Kickstarter video when Stephenson refers to it as, y'know, "Guitar Hero with swords."

"I've been playing some games as long as they've been around. I'm aware that the market's filled with people who play them avidly, and I'm not one of those people. But starting with Pac-Man in bars when I was a younger man, and continuing through the developing systems I've been playing games."

That sounds great, for sure, but the team's got to raise the money first. "The initial response was pretty spectacular," says Stephenson when I ask him how the crowd-funding is going. "It's apparently a pretty common pattern with these things that, in the middle of the campaign, one goes through a sort of plateau. We've been there for a while. But it continues to climb steadily, and we've been using that time to get to know our donors a little bit and figure out what they're interested in.

"As soon as I finish this interview, I'm going to go help edit together another update. We did an announcement with Razer about the Hydra hardware, which we hope will bring us some eyeballs, too. As far as we know, we're on track." A quick snigger. "I think that because it was pretty splashy at the beginning, a lot of people just assumed that we had hit our goal. Which we haven't."

A big part of the Kickstarter's appeal has been those videos that Subutai has made, in which the novelist, elegant in black, wanders through a parody of the creative environment, explaining his ideas while juxtaposed with increasingly bizarre backdrops. Stephenson's dourly comic, with lovely timing and a sharp sense of the absurd that comes straight from his books. Although the videos are funny, it's hard not to love the world of imaginative industry they conjure up: everyone hanging out together, working on little bits and pieces, doing their own things. It feels like the best kind of college, or academy - or perhaps circus.

I ask Stephenson if playing the ringleader, or at least the public pamphleteer, comes naturally to him. "Yes and no," he frowns. "My normal habit is to be a solitary writer: get up, live a very quiet life, and work alone all day long. But that's interrupted by these sporadic book tours and other types of efforts where I have to be kind of an exhibitionist for a while. I used to mind those things a lot more than I do now. I've sort of become inured to it. I did theatre when I was in high school, and I was sort of an actor. I was more of a techie - more of the guy who runs around back stage and sets up lights - but I did a bit of acting. Like many introverts, I'm capable of adopting a persona and going out into a public place if there's a reason to."

Clang's Source demo looks endlessly intriguing. It should be fascinating to play.

One of the funniest moments in the videos comes during an analysis of the success of shooters and gun games, where Stephenson states, "You people love this," with a gentle, smiling emphasis on you people. Isn't he one of us people, too? When I ask him about this, what follows is a brief games biography, and an unexpected glimpse at the Stephenson exercise regime. Pencils out if this is your sort of thing.

"I've been playing some games as long as they've been around," he says. "I'm aware that the market's filled with people who play them avidly, and I'm not one of those people. But starting with Pac-Man in bars when I was a younger man, and continuing through the developing systems I've been playing games.

"I actually got into a period some years ago when I was playing Halo too much and I'd suddenly realise it was three in the morning. That sort of pattern. Time would go by without my knowing it. At the same time I was trying to get into more of an exercise rhythm. I found that when I was on a treadmill or an elliptical trainer, the opposite phenomenon would happen, and that every minute would seem like an hour. I just sort of hated it. I couldn't make the time go by fast enough, so I decided to combine those two things, hooking up an Xbox in front of an elliptical trainer and playing the most absorbing addictive games that I could find. That really worked well. I'd start up, get going, and suddenly 45 minutes would have gone by on the clock. I would have gotten a good work out but I'd still want to stay on longer, to finish the level."

When it comes to the other part of Clang - the swords - Stephenson's been a fan for a while - even before they cropped up in Snow Crash, where they were often wielded by pizza delivery ninjas. ("But swords need no demonstrations.") "I had the usual very common interest in swordplay from being a kid," he explains.

"When Star Wars came out, I was terribly excited to see they were using swords, and I remember reading Dune and being hugely impressed by the fact that Frank Herbert had come up with a somewhat convoluted excuse for why they had to fight with blades. In both cases, here's this universe where they're sophisticated enough to have interstellar travel, but there are these reasons for why they're fighting with swords."

"When Star Wars came out, I was terribly excited to see they were using swords, and I remember reading Dune and being hugely impressed by the fact that Frank Herbert had come up with a somewhat convoluted excuse for why they had to fight with blades. In both cases, here's this universe where they're sophisticated enough to have interstellar travel, but there are these reasons for why they're fighting with swords. That was always part of my pop culture fan mentality. I took classical European fencing when I was in college for a bit, and I studied Kendo after college. I always maintained contact with that world."

That said, it wasn't until he was working on the Baroque Cycle - a series of historical novels so weighty they would probably be quite useful in a fight if you couldn't get your hands on a rapier - that he began to take swords a little more seriously. "That's when I began trying to educate myself a little. That went slowly for a while until I made contact with the historical European martial arts community at which point it became easy to learn faster."

Why a game, though? Simply put, it's because Stephenson believes there are no good sword games around at the moment. No games that revel in the complexity of the weaponry and the techniques involved in the same way that shooters do. Is this simply down to controls and controllers? A matter of buttons and triggers? Stephenson nods.

"I'd say it's mostly buttons and triggers, yes. It's a far simpler thing to just put a crosshair on your HUD and move it around with a thumbstick and shoot at something. That's just an artefact of how the hardware was made. I understand why it is that way. But where we are right now, we're on the threshold of being able to do much better, and the hardware universe, five years from now, is going to look very different from what we have today. It just seemed like the time to do this."

This still isn't going to be very straightforward, though, and Stephenson's more than aware of the difficulties his team faces. He's not blundering into games arrogantly, in other words, assuming that nothing else in the world can be as tricky as writing a novel - although some of his own novels are as tricky as you like. Amongst the challenges Clang's up against are things like body awareness, like recreating a physical sense of impact with a motion controller, and - oh yeah - like reading your opponent and making quick decisions based on that reading. This last issue is knotty indeed: Subutai wants to make sword art accessible, after all, but it doesn't want to sacrifice the nuance that makes it rewarding.

Stephenson offers a typically clear-headed engineering approach to this one. In fact, he makes the ancient art of getting stabbed in the nuts sound like Chess, or Go. "There's a move tree that you could draw out for any well-understood sword art," says Stephenson, head bobbing slightly as his treadmill trundles onwards. "Player A makes a move; it leads to a change in the situation. Player B is presented with at least one choice they can make in response to that. If they make that choice quickly enough, we go to a different part of the move tree, and if they wait too long, something bad happens.

It must be nice having Gabe Newell as a chum.

"That can all be mapped out by people who know enough about sword arts. The game building project then becomes all about attaching an interface to that move tree. An interface that is reasonably intuitive in the sense that the movement you make with you hands is something reasonably close to the movement the swordfighter is going to be making.

"I wouldn't call any of this a headache," he continues. (I had just called it a headache.) "The reason we keep making an analogy to shooters is that this has all been done in the case of shooters. I mean, these games have become unbelievably complicated, and gamers like that, right? Serious gamers quickly become bored and dissatisfied with anything that doesn't offer that level of complexity. The same ought to be true of swords. And although the move tree might look complicated if you plan it all out on a piece of paper and hang it on the wall, the fact is that each individual decision point in that tree is very easy to understand. It's like: you need to block that blow, and then you need to do something. And then when we see it all on screen from the point of view of the actual swordfighter, it's about as intuitive as it gets."

On top of that you can chuck a UGC pipeline. This sounds pretty exciting, actually. "Our first objective is to embody one martial system, which is Fiore's system. As anyone knows who's done computer programming, when you've done a thing once, you've created the tools and the infrastructure you need to do similar things over and over again. In order to do Fiore, we've got to create that toolset, and at that point the best way to make this thing work is to let other people make use of that toolset to make user-generated content. It could be something as small as hats, I guess, but it could mean embodying some other martial arts system, some other weapons style - if people want to do that much work." It'll most likely be hats.

It should be clear by this point that Clang really is a game about blocking and parrying, rolling and lunging. It's (perhaps blessedly) free of narrative and deep characterisations, in other words - although as we'll see, some of that stuff might be on the way. This is super interesting, if you ask me. Did Stephenson feel the need to really switch his creative approach when shifting, even briefly, between books and games?

"Writers for a long time have reached out beyond just book-writing and approached different media," he argues. "Since the beginning of motion pictures, for example, writers have made the trek to Hollywood and tried to write screenplays. It's a natural impulse to want to try your hand at another medium, and perhaps a more collaborative medium. That's all perfectly normal. It happens that, during my career, the film industry was eclipsed by games. I don't think they've actually quite cottoned on that they've been eclipsed. If you look at the money involved, the hours spent on games as opposed to watching movies, it's clearly happened. That just raises the question: if I want to try my hand at a different medium, why shouldn't that be games as much as TV or movies or what have you?"

"Games have become unbelievably complicated, and gamers like that, right? Serious gamers quickly become bored and dissatisfied with anything that doesn't offer that level of complexity. The same ought to be true of swords."

But when Fitzgerald or Dorothy Parker or whoever you want to mention left New York for Hollywood and started scripting movies, they were still writing stories. They were still dealing with a predominantly narrative-driven medium. Games are not necessarily a narrative medium, and Stephenson's is not a narrative game. Was that another interesting layer of challenge for him, especially since his books tend to offer stories within stories, plots within plots, mobilis in mobili? Or was it second nature, perhaps? He is, after all, a writer who builds worlds, who constructs his novels around systems.

"It's true that science fiction and fantasy writers have this attribute that they are world builders," he says. "That's not true of some other writers like Fitzgerald or Parker - not to complain about the quality of their work at all. So it's always been the case that fantasy and science fiction writers are world builders and fans of this kind of fiction are looking for that. That's a long-established trend.

"To that extent, it's a pretty easy fit: this game is rooted in a built world that we're still building. That aspect of it hasn't been emphasised during the current campaign. That's because we're trying to raise what is really a very small amount of money by game industry standards. In order to be honest with our donors we have to be clear about what we can and can't achieve with that budget. At Subutai we just want to get a workable mechanic going and then if we can turn that into a sustainable business, for us, given the skillset we've got, integrating that into a much bigger universe is going to be second nature."

Subutai Corporation is the last piece of the Clang puzzle, then. Founded in 2010, it's a kind of cadre of interesting, creative people like Stephenson, and its objective is to build media franchises. That makes it sound a little clinical, so here's something from the website instead: "We start with a story, and then we build a world." It all ties up rather neatly, I guess.

The current story is concerned with the Foreworld, a fictionalised medieval Europe pretty much stuffed with adventurers and vagabonds. It's already spawned the Mongoliad, a serial novel that's also a smartphone app, and now it's birthed Clang - or at least it's trying to. "The very first Foreworld thing we came up with was a piece of filmed entertainment that we're still pursuing," says Stephenson. "At that time, though, we got some advice from a number of quarters that we should be working on other forms of media as well. We very early fixed on the idea of trying to build a game. We actually began work doing some motion capture work and preliminary game design almost immediately. It's been a slow background process for us. It's actually been integral to our vision of the project from the first weeks. We chopped out a particular piece of timeline where the game is going to be set, once it gets big enough to be a proper game."

So as the Kickstarter ticks down and the money piles up, where is Clang at the moment? And how does Stephenson fit into the project? "The process we've followed until now is that we've collected an initial round of seed money with which we've hired the people needed to put together a demo game," he explains. "What you're seeing in the videos, it's running in Source, it uses some prototype Sixense controllers. The next step would be to bring in a proper engineering team and get them employed in a stable and satisfying way, and build the demo out into something that ordinary people could play in a satisfying way, too.

"My role in that is going to be largely to get out of their way," he laughs. "We borrow a lot from Valve. We don't have a formal business relationship with them, but we benefit from advice and seeing how they do things. One of the very well known principles about how Valve is managed is this notion that people there are largely self-managed. It's not a hierarchy. That's an idea we'll be stealing from Valve and putting to good use. That's a way of saying that placing me at the top of an org chart isn't the way for this to succeed. The way for this to succeed is for us to use the Kickstarter money to hire people who are self-motivated and self-managing. At that point I'll become a resource that can supply information and ideas when they actually help.

"I don't consider myself a game designer, really," he admits. "We'll get a proper game designer as budget permits. Game design is more than throwing out a few ideas. It's an involved and technical process. I guess my view of the thing is rooted in just a low level nuts and bolts way of thinking about how the game would work: what's known and what's being discovered about historical swordsmanship, how to build a UI that captures some of that, and how to convey a sense to the player of what it was like, back in the day, when these martial arts were an integral part of the power structure of Europe."

I ask Stephenson what it's like to be working with designers and software engineers and computer techies after all these years of writing books about them. "In a way this answer would be more interesting if it were difficult," he sighs. "You know, if I'd had problems and crazy stories to talk about. In reality, there's a huge cross over between people who are interested in games and people who are interested in sword fighting and in the whole medieval action environment.

Friends Like These Gabe Newell's a friend of Stephenson's and an investor in Subutai - and he also pops up in a Kickstarter video. It's a delightful performance, even if it proves that acting is one of the few things that flat organisational structures and comprehensive user-testing can't really help you with. Stephenson's chummy with Bungie, too, another business located not far from his home in the Pacific North-west: his team has picked up pointers from both studios, even if links remain entirely unofficial.

"It's almost second nature to a lot of game people to want to talk about this. And in general, when game people find out what we want to do, it opens the floodgates. Suddenly I get to hear every thought they've ever had on the subject of swords in games. I hear a lot of the same things over and over again, which is not surprising, and it makes me feel like we're headed in the right direction. Scratch a game geek, and you'll find a swordfighter wanting to get out. It's just a matter of supplying confirmation that there is something there, that these historical sword arts are well documented, and thanks to the efforts of people around the world, they're being researched and brought back to life again. They're just sitting there waiting for people to come and embody them in games."

Ultimately, is there more to Subutai than Clang and the Foreworld, though? Is it a lark and a folly, or is it a canny gamble on where entertainment might be headed as novels, films, and games continue to converge? "I've been having dealings on and off with the entertainment industry since 1984," says Stephenson. "My first novel was actually optioned by Ridley Scott. For that long, I've been making the occasional trip to LA and dealing with that industry. During that time, that industry has come to include games. With that as background, another bit of advice we're aping from the gang at Valve is, maintain creative control over your IP. Don't sell off rights to someone who can go running off and do whatever they want. That's the principle we've been trying to follow.

"Subutai was basically created as a vehicle for carrying out that strategy, and for conducting a big experiment with that strategy. What we're trying to do is get to a place where the books, game content, and any filmed entertainment that comes along later will all be rooted in a central team and will be recognisably coherent. We're accustomed to this thing where a movie comes out that's based on a comic book, but it's really different than the comic book and you can tell that different people worked on it. Then a game comes out based on the movie, and it's different also. These things just aren't being developed in a coherent way. We're trying to perform this experiment to see if we can start with an idea and develop all of these things in a coherent way and actually have it be sustainable. And a lot of that boils down to how it's financed. When you take lots of money from people, they get creative control whether you like it or not. That's why we felt Kickstarter was a good match for our game plan."

I suspect Stephenson's offering much more than coherency, though, and if anyone is going to meddle with the boundaries between media, I'm pretty glad it's him. After all, there's little of the old hierarchy visible when he speaks about games: at home, they may still be reserved for the treadmill, but with books like Reamde, they're steadily creeping into the fiction, just as Mongoliad's fiction will be creeping into Clang.

On top of that, Stephenson's world-building experience seems to have left him with an innate understanding that game authorship is very different to novel authorship. As a game designer - on the rare occasions you can get him to admit that's now a part of his job - he seems fairly clear that you write games with mechanics and with UI, and collaborate not just with the design team or even Kickstarter backers, but with your players, too - throughout the course of the development and beyond.

When it comes to games, in other words, there's a bit of novelist in all of us.