Initially, the premise for Heaven’s Vault sounds like a typical video game. You play as a young woman named Aliya Elasra, accompanied by her temperamental robot Six, and together you explore a series of moons that were once home to a mysterious ancient civilization. But the ruins aren’t filled with violent aliens to kill or powerful weapons to discover. Instead, what the civilization left behind is words, and it’s your job to figure out what they mean.

Heaven’s Vault is the next release from Inkle, the British studio best known for the globe-trotting adventure 80 Days. It’s a 3D open-world game built by a team of just eight people, though the scale of the world — or worlds since Heaven’s Vault takes place across a network of moons — isn’t the most impressive thing about it. Instead, it’s the language. In order to make players feel like true archaeologists, Inkle created an entirely new hieroglyphic language from scratch. At first, you won’t understand a word of it, but as you play, you’ll not only start to understand the words, but also the society that created them.

At GDC this year, I had the chance to explore a single moon in the game, which took about an hour. Playing Heaven’s Vault feels like moving through a three-dimensional graphic novel; while the world itself is 3D, the characters are flat, resulting in a curious flickering effect as you move. It looks a bit like you’re flipping through the pages of a book, and it took a few minutes for me to adjust. As I trekked across a lush garden on the moon, I came across strange monuments, sort of like thick, metallic beams jutting out from the ground. Each had an inscription written in the game’s alien language.

The first time you see a hieroglyph, you essentially have to guess what it is. The game will show you a pictorial, and then give you a few options for what it might mean. A symbol could mean either “temple” or “garden,” and, initially, all you have to go on is the context of where the symbol is and what it looks like. If you guess wrong, you aren’t punished. In fact, the game lets you carry on thinking that could be the meaning of the word. As you explore, you’ll keep seeing symbols repeatedly and learn new ones that can give you a better idea of what others mean.

“That feeling of not quite being sure is important.”

Eventually, if you’ve guessed wrong, Aliya will realize that it isn’t right, and the definition will be reset. By that time, you may have worked out what it really means by discovering other hieroglyphs or by learning something new about your location. It’s a system designed specifically to make you feel unsure and thus more like a real archaeologist. The game’s creators want you to fumble around. “We deliberately delay that process a little bit so that it goes on for slightly longer than you might be comfortable with because that feeling of not quite being sure is important,” says Inkle co-founder Jon Ingold.

The language itself has around 1,000 words, and the team describes it as being “logically constructed.” The idea is that the symbols aren’t random; each has a meaning, and that meaning is always the same. The language is inspired in part by other image-heavy languages like Cantonese and German, where many smaller words are often combined to create a larger concept. “As you find different words that use the same glyphs, you might get the idea of related concepts,” Inkle’s other co-founder, Joseph Humfrey, explains. “But we don’t ever tell you exactly what the glyphs mean. Sometimes you’ll come across an inscription that is literally impossible for you to solve.”

The game does give you some context. Heaven’s Vault’s characters are very chatty. Aliya will speak her theories out loud, and she’s constantly arguing with her robot assistant about something. These discussions can give you a better idea of where you actually are, and what the words engraved around you could mean. In my case, I thought I was simply in a beautiful garden, but it turned out to be an ancient burial site. This realization made me completely rethink the meanings of the glyphs. Understanding the language is a sort of puzzle for you to solve, but it’s also a storytelling tool. The more you learn about the glyphs, the more you discover about the alien civilization that created them. “It’s worldbuilding in a very interesting way,” says Ingold.

“I don’t think this is a game that linguists are necessarily going to like.”

While the language itself is real, the team admits that, in order to make it work for the purposes of the game, it’s not exactly the most functional language. “It’s complete in the sense that it’s fully logical, but it’s also not a super useful language,” Humfrey explains. “We have around 1,000 words, which is just enough to be useful for the purposes of the game.” He likens it to Guitar Hero for linguists: it’s enough to make you feel like you’re doing the job, but it cuts out a lot of the more tedious busy work. “I don’t think this is a game that linguists are necessarily going to like,” says Ingold. “But that is the job of game design. You have to distill these things down.”

Heaven’s Vault is launching later this year on PC and PlayStation 4 (an iOS version is also in the works), and it’s a game that has understandably wormed its way into the heads of its creators. After the demo as I stood up to leave, Ingold handed me his business card. But instead of a job title, it had a symbol from the game’s language. The pictorial isn’t actually featured in the game, according to Ingold, but he wanted to work out how to say “writer” with the glyphs. “That translates to ‘Person who speaks without speaking,’” he told me.