One of the most inspiring things about humanity is that no matter where we end up, we can find a way to thrive. Take, for instance, the setting of Threshold, an indie game by a developer who previously worked on Deathloop and Dishonored. Threshold takes place on the peak of a high mountain, where you play as someone embarking on one of the most stressful maintenance gigs available. I watch the trains go by, and make sure that they run on time. The air is so thin, I often struggle and choke my way through a shift. My predecessor is buried nearby, and my co-worker is just relieved that someone is there to share the burden.

There’s a country-based difficulty system, or at least the Steam page advertises one. I chose Canada, and the game begins with an ominous display of my home country and flag. I load into my little worker’s room and spot a shirt that says “I love Ottawa.” As a proud Torontonian, I frown. This game is already insulting me. This is true psychological horror.

I spend my first half hour or so in Threshold just going through the motions of the job. I’m allowed to pick a two-letter name: Bo. My colleague, Mo, walks me through the job. I blow a big horn when the train slows down, and that spurs it to speed up. Then, I take a punched ticket and exchange it for a vial of air. When I’m struggling to breathe, that vial of air is a lifesaver. Unfortunately, I have to bite down on it, leaving me renewed but spitting out blood.

Mo teaches me a few tricks to make the shift a little easier. I can go down to the sluice gate and scrape off some calcified goop, which rewards me with a second ticket. The station is laid out in the most inconvenient way possible. I have to loop around buildings and take side paths. If whoever set this station up took even a few minutes to add a couple of doors, I could shave off minutes at a time for each task. But they didn’t, and that feels intentional. Like the air vial that is designed to break upon biting, whoever set this arrangement up is fine with putting little hooks and catches into each step.

Regardless, I work hard, and before long I have a little stockpile of air vials. Maybe it’s because of that country-based difficulty system, but I’m breathing easy. That’s when Threshold opens up. There are secrets hidden all over the map, and digging into them advances the story. I find a dead body, for example, and decide it’s worth mentioning to Mo. I find a secret door that I can open with a whistle, and it brings me to a wondrous place with endless air and the chance to ask questions about things I’ve found on the job site. Part of me wants to stay here forever, but the train has to run on time.

Threshold’s simple PSX-style graphics and lack of music mean that keeping the train running and collecting tickets becomes an almost meditative experience. Over time, I fall in with the rhythm of the train, the grinding of gears, the sound of a ticket noisily printing. It takes just over an hour to beat Threshold, but the game’s hidden secrets and multiple endings make it worth revisiting.

Threshold was released on Nov. 19 on Windows PC. The game was reviewed using a download code provided by Critical Reflex. Vox Media has affiliate partnerships. These do not influence editorial content, though Vox Media may earn commissions for products purchased via affiliate links. You can find additional information about Polygon’s ethics policy here.