VR experiences are a bit like magic tricks. If they work, they can leave you open mouthed in wonder, pointing into the air like an incredulous 6 year-old. And if they don't, you're just left with someone waving their hands around in an empty room, feeling slightly embarrassed.
One of the most convincing VR experiences is Job Simulator, where you manage a cartoon corner shop in what sounds like a parody of a game. Everest takes a polar opposite approach.
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In place of a small-scale shop is Mount Everest. Simulating the banal is replaced with emulating what must be one of the most exhilarating sights on Earth, the top of the tallest mountain. Ambitious, much?
Such scope makes it easy to point out the holes in early VR hardware, but Everest deserves to be on the list of "must-experience" software for HTC Vive owners, alongside underwater 'experience' theBlu.
Experience versus game
This isn't a game. Like a lot of the most impressive early VR software, it's more a challenge from developers that says, "Bet you $10 we can suck you into VR."
It did a trick on me.
It splits a trek up Mount Everest into five scenes. I started at a camp, presumably near 'base camp' where the climb really begins on the actual mountain. The snow is thick, and in cinematic style the morning mist gradually clears to expose the sort of view I frankly can't afford to see on my holidays. It's not budget airline fodder: grand vistas of peaks worthy of a BBC documentary series.
A couple of typical mountaineering types talk by a tent about how they didn't manage to get up to the summit last season. They're gagging for the summit. This is the intro sequence of your Everest VR experience.
At this point I was still warming up to the Everest chill, all too conscious that a PR person was probably taking pictures of me, and that the important industry contact also in the room was probably thinking about what an idiot I looked.
At this moment of peak awkward self-awareness, Reynir Hadarson, creative director of Everest developer Solar asked me to get down on my knees and crawl into the virtual tent. I was't keen. After all, it was the sort of thing you'd buy from Argos advertised as a "three man" tent, only to find it's like camping in a pair of cycling shorts.
I gave in. Once I'd scrambled into the thing, I understood Hadarson's reasoning. The whistling wind was suddenly deadened, and while I knew I was really crouching in some old library room in the Royal Geographical Society by Hyde Park, some part of my brain still innately knew where the edges of the tent were. Made of polygons as they may be, your senses believed the walls are there on some level.
This is where Everest starts its VR indoctrination. Getting your ears and hands involved is how it tricks your senses into thinking what you're seeing is a tiny bit real. Next up, Hadarson got me to pick up an oxygen mask on the floor using the Vive controller, bringing right it up to your mouth.
"Photorealism alone is not enough for immersion, says Hadarson. "There are certain things that help. One is having 'hands', being able to do simple things, that gives you a sense of agency in the world."
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Other bits of the Everest experience I tried include the ultra-narrow Hilary step, where mountaineers have to walk in single file, as the ground falls away to nothing just a couple of feet away from you. Here you use the controller to drag your clip-on carabiner along the guide line, shuffling along carefully like you're in a conga line.
At the summit you also get to plant your own flag. You may not have earned it, but it's still pretty cool, kicking off a dynamic weather shift that had me marvelling at the sky in a way no game has done for a good few years.
The part of Everest you have to try is peering over the edge, to see if your stomach turns as vertigo kicks in. Mine didn't but the way the simulation left me tip-toeing towards those cliffs does suggest some of the magic was working.
Hadarson also talked a little about how Everest isn't out to freak you out. "For Everest we wanted to have the broadest reach possible," he says. You don't fall off cliffs, you don't see arms and legs in front of you to root your in the environment. It's a benign and relaxing experience, not a test of your will.
Part of this is down to a technical issue. "We can't track your legs," Hadarson explained. "Simple things like footstep sounds‚Ä¶ we trigger by the acceleration of your head." This isn't something I twigged while 'playing', though. The simulation is a consistent one.
The environment is convincing too, which makes me wonder how much more you could trick your mind just by ramping up the AC and sitting a powerful fan in one corner of the room. Tricking more senses can only mean more effective VR.
A Hollywood marriage
Solfar has worked on Everest for a year, in association with RVX. "Two years ago [RVX] worked on the movie Everest," says Hadarson. RVX is a company that produced some of the epic effects shots in that film. "We talked to them and discussed the experience of recreating the whole thing." And here we are.
Before I knew about RVX's involvement, Everest VR gave me flashbacks to that movie. The film is exciting and gripping even though it functions as much as study self-involved, narcissistic mountaineers as a natural disaster thriller, and the scenes here seem just as real.
You can walk freely around each area. They are far larger than the HTC Vive sensor area of around 3-4m by 3-4m (perhaps 20m long or wide), but you can zap around each play zone using an increasingly familiar mechanic: hold down on the pad on the controller and point.
Of course, the more you indulge in this, the more it takes you out of the experience. Hadarson thinks we'll see immersion-improving hardware changes before all that long, though. "In two years from now it'll probably be a very different kind of hardware from now, probably without the tether." While the Vive offers the most immersive home VR you can get right now, the tether that connects the headset to your PC does get in the way.
Yanking it on it doesn't half bring you 'back in the room'. We're not quite ready to plug into the Matrix 24/7 yet, but that's no bad thing.
Everest will be released for HTC Vive soon, with versions for Oculus Rift and PlayStation VR planned. Solfar is also set to return to work on its VR game Godling, originally shown off at E3 2015, which casts you as a baby deity not quite in control of its destructive power yet. Sounds like a lot of fun.