A cute little proof-of-concept game has picked up attention on Steam in the past few weeks: Frostrain, a card-matching game about conducting a train of apocalyptic survivors through a frozen world ala Snowpiercer. Getting stronger requires you to build up a hand of the same cards, all of which represent train cars to expand your new demesne with.

At the same time you have to set a course through the wasteland outside, navigating by terrain and such between nodes that represent snowfields, polluted wastes, cities, and famous landmarks.

Frostrain is part demo, mostly proof of concept, and it’s entirely free. It was made by an amateur team called Stewdio, who by their own admission just wanted to put something playable in front of people. Admirable, in my estimation, though some folks were hoping Frostrain would have a deeper future.

“As a team of five beginners in the game development industry, we would like to explain our situation,” said their post on Steam. “This is our first game release and some of us are still in school. The whole reason we got together to make the game in the first place was to be judged on our abilities by our users, not on the basis of ‘let’s make a lot of money off of this!’.”

“This is why we planned to release the game for free from the beginning and why it was developed in a short timeframe of two months. As a result, several parts of the game were left unfinished, as some players may have noticed,” they said.

Frostrain currently has three conductors to unlock and play as—a solid by-the-books train engineer, a hard-nosed surveillance state leader, and a brave populist who lead an uprising against the former captain.

You can find Frostrain on Steam, where it’s free.