Microsoft's Kinect motion sensor, a peripheral camera for Xbox 360 that tracks movement for video games, has been a great success. The hardware add-on sold more than 10 million units and 10 million games in its first 60 days on sale late last year, with Guinness World Records branding it the fastest-selling consumer electronics device of all time as a result.
Kinect has been pushed as the next big thing in games from the very top of Microsoft, with CEO Steve Ballmer himself saying the device makes Xbox 360 more than a games console.
But despite the attention, one thing has been glaringly missing from the entire Kinect program: it has no core video games.
In the games trade, "the core" occupies what you might think of as traditional games: shooters, driving and fantasy titles all fall into the category. The people that play this content - 18-35 year-old men, largely - are Xbox 360's mainstay, and one of the biggest reasons Kinect ever existed: the camera's so far been aimed at the casual and children's markets, giving 360 more overall reach.
The core, however, isn't happy with its lot. Microsoft knows it, and thus Kinect is about to begin its trip into the more involved games space with Fable: The Journey, the latest from celebrated British developer, Lionhead Studios.
The Journey, the fourth Fable game and the first for Kinect, sits the player in a horse drawn carriage, using arm motions to cast spells and smack reins in a free-roaming adventure spanning hundreds of miles.
It's a fantasy game set in the world of Albion, a land well-loved by enthusiasts, and it's one of the first titles to solve Kinect's greatest problem: that of allowing players to sit down.
This has been one of the primary factors Kinect titles have leant so heavily on the family dancing or jumping in front of the TV up to this point. So far, Kinect has not been able to properly recognize players in seated positions.
A stepping stone game to Fable: The Journey, a quirky Old West shooter called The Gunstringer, releases next week and will, finally, allow Kinect players to sit.
Speaking to me at German games show gamescom in August, Microsoft Kinect evangelist and studio manager Shannon Loftis explained why The Gunstringer is such an important bridge game for Kinect's stab at the core.
"First of all, it's a shooter, but the shooting mechanic has been reimagined from the ground up for Kinect," she said.
"But the thing that nobody's talking about, and yet it's a critical piece, is that you sit down to play The Gunstringer.
"Core games are deeply immersive and they last for a really long time. People play for many, many hours, and that's a difficult thing to do when you're up and jumping around."
The Gunstringer, though, is a lead into 2012's main events for Kinect's core initiative, more of a test than a serious effort to sell Kinect to traditional gamers. Fable: The Journey will be the first real mark of Microsoft's commitment to the core. It's not for kids.
"Like everyone else, I want a game that will make the hairs on the back of my neck stand up," said Lionhead boss Peter Molyneux in an interview earlier this year, speaking after the game was announced at the E3 games show in Los Angeles.
"That's what the potential is here. I predict this time next year at E3, people will be saying completely different things about Kinect. It wasn't that long ago we all thought that mobile games were rubbish."
And Fable isn't the only upcoming Kinect game to be aimed at the less childish gamer. Steel Battalion: Heavy Armor was announced over the summer, planting the player in a giant robot in what was described to me at the time as a "gory, human drama".
A far cry from mums and dads playing cartoon football with the kids. Kinect is coming to the core. Who knew sitting down could be such a plus?
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