How do you draw "privacy"?

The first thing Mountain asks me to do is to scribble a series of black-and-white pictures in response to various, seemingly randomly generated, weighty prompts. I've read about other players' experiences with Mountain, a new game for PC, Mac, Linux and iOS, and so I know that so far there's no discernible link between these answers and the game that they ostensibly generate. I take a stab at "privacy" and continue on.

Created by David OReilly, a 3-D animation artist perhaps best known for designing the videogame played by the main character in the sci-fi romance film Her, Mountain is a game about nothing. Or a game about everything. It is a game in which, once you're done answering these questions, you're left staring at a floating mountain on your monitor, on which weird, unexplained events occur, and nothing you do seems to have any impact. (I think.)

I haven't even gotten to the mountain, yet. I'm still stuck drawing "Happiness." How would I even define it? A personal life goal? The name of some current or former lover? A warm puppy? A warm gun? I'm living out a Simpsons joke. I know it doesn't matter, that I can draw literally anything to reach the main game, yet it feels weirdly profound nonetheless, like the game deserves an answer, or I do.

I settle on an idea I deem satisfactory and click Done. "Patience," Mountain says to me: My mountain is being generated. A lonely conical shape comes into view, like a massive, otherworldly hand has scooped up a single peak and set it adrift in the air.

You can rotate the camera at will, zooming and panning to focus on singular details or take in the eminence as a whole—or leave your mountain to its default leisurely spin. Keyboard presses produce mild musical tones, but engender no response from the earthen pile on the screen. The game window can't be maximized, but it does save automatically. Like life itself, there is no undo feature.

Your mountain spins along, subjected at random to the fantastical whimsies of life and other things. A tree may sprout on your mountain, and it may grow into a forest or wither into nothing. Suns rise and set. Rains fall. Seasons pass. Like a god that doesn't exist, you are powerless to pause the cruel march of time, alter the course of history, or explain why a giant clock just crashed like an asteroid into the side of your floating lonely peak.

My mountain periodically spouts bits of existential nonsense to me, signified by a brief piano-tone. "I'm basically opposed to this sweet day," it says. Its sides are green with grass, prickled with a cluster of autumn trees under a sunny sky. Why would it be opposed to this? I don't know why my mountain feels anything.

There's a tire embedded in my mountain now. No wait, it's a giant top hat, turned on its side. I can't explain why it's there, or when it arrived—probably during some moment when I stepped away from my computer, or pushed the game window into the background, distracted by real life. You might miss something if you don't watch your mountain for every second of of every day. But you can't watch it all the time. We can't see everything all the time, and we can't expect to, either.

I close my mountain, silencing its constant quiet din of rustling wind or falling rain. Even relegated to the back of my computer's window stack, Mountain is with me, its ocean-like sounds now familiar to my ears. But with the window closed, I am met with naught but eerie silence. I miss my mountain. I open the program again.

"Everything's fine," it says to me, as the side of my mountain with a half-buried horse rotates into view. The horse has been with me for a while now, the second thing to plummet from the sky into my mountain following a giant message in a bottle. I take comfort in my mountain's newfound contentedness.

This is my mountain. There are many like it, but this one is mine. WIRED

My mountain has a way of telling me how I'm feeling. Not that it always speaks in the same mood as my own, or that my mood reflects what it says, but in the way I react to its arbitrary musings. When I'm content, I enjoy its happiness and am perturbed by its petulance. When I'm feeling sour, I revel in its bitterness and balk at positive meditations. Like how flipping a coin can help make a decision, not by following the coin's outcome, but in how you feel in response to the coin's arbitrary mandate.

Something just happened on my mountain. I'm not quite sure what. I left it running in the background while working on something, and by the time I tabbed over at the cue of an odd noise, all I found was a snow-covered peak adorned with a small jumble of pink, like a small whirlwind of rose petals, that quickly dissipated. Now there's just a small reddish stone at the core of where they flurried, a short distance up from the half-buried top hat (which now sits upright for some reason).

I make a discovery. While fruitlessly attempting to tap out a dulcet melody, I hit a key that seems to prompt one of my mountain's introspective thoughts. At first I think it coincidence—nothing else I've done has elicited any sort of response—but I hit the key again moments later, and my mountain emotes again. At first I feel this cheapens the experience, as if the comfort I took in its existential reflections only held meaning due to the game's random collection of chaos. It bothers me so much that I don't open Mountain for more than a week.

But when I return to my mountain, it remains silent. For far longer than any period of time between messages before. I grow worried, thinking something is wrong with my mountain. I fill with unease at the lack of remark. I press the magic key, the one that commands my mountain to pull something from within its mind, and all is right once again. I am not just alone with my thoughts; my mountain is with me.