The Witness is a game about communication. It's a game about understanding the world, and about having a conversation without saying a word. The game, in development for more than six years at a cost of more than $5 million, is the long-awaited follow up to indie godfather Jonathan Blow's Braid.

It's a quiet game, literally (there isn't any music at all) and thematically. It's subtle and introspective. It's a puzzle game, but so much more than that, despite being a game about drawing a line through a grid-shaped maze, over and over and over again. And it's great.

In 2008, Blow released Braid, a puzzle-platformer with a time-rewinding mechanic, for Xbox 360. The game was an instant success, going on to sell millions of copies across multiple platforms. Along with a few other notable titles, it showed that indie games could be more than half-baked mechanics and crudely-drawn blobs from wannabe designers. Its success was chronicled in Indie Game: The Movie, which set up Blow as one of the few "indie game auteurs"—designers with the style, vision, and ability to produce consistent, exceptional work.

Blow announced his follow-up in 2009. The Witness, he called it, would be a 3-D puzzle game set on a large, open-world island. It's finally coming out for PC and PlayStation 4 on January 26. Why'd it take so long?

"Because it's big," Blow says, "and we're a small team."

I'm chatting with Blow over tea on a sweltering day in San Francisco. Two weeks earlier, I'd received a near-final build of The Witness. After around 25 hours of play, I've completed a large portion of the game's curious panel-based puzzles. And yet, I feel I've barely started.

The Witness's core mechanic involves solving a series of puzzles that require you guide a line from one point to another through a grid-like maze. The panels progress in difficulty by adding rules—objects within the grid that must be separated, or isolated, or grouped together. Sometimes your line must form a particular shape, or follow a certain path. It's a puzzle game, but it doesn't look like most puzzle games. Take Sudoku, for example—that's just about giving your brain something difficult to figure out.

"That's fine," Blow says, "but I wouldn't have spent six or seven years making Sudoku."

Jonathan Blow

In actuality, The Witness is a very long and intricate exploration of possibility. The island is divided into a number of sections. Each is the exploration of an idea, and fully progressing through that idea activates a golden box, illuminating one of seven beacons required to access the island's central mountain.

As you progress through a section, you learn from each puzzle how to solve the next, and each is more complex than its predecessor. Explaining your thought process for solving a section's advanced or final puzzles would require several sentences, yet the game has said nothing to you. "One of the subjects of the game is non-verbal communication. To see how sophisticated are the ideas I can build up without saying a single word," Blow says.

The game's open world not only lets you roam freely from one puzzle to another, but also tackle its major sections in any order you desire. If one section proves difficult, if not entirely too hard, to grok, many more puzzles are but a 20-second walk away. That nonlinearity proves key to progression. When I faced a puzzle I couldn't solve, most often it was because I had not yet learned how to solve it. I needed to move elsewhere and learn, from another puzzle, how to solve what was in front of me.

But it's in this way that The Witness is actually cripplingly linear. At the start, much of the game's world is gated, locked not by keys but by knowledge not yet learned. You must progress through each section in the order it's given to you, otherwise the puzzles would make no sense at all.

"What's happening as you play is this stream of communication—it's nonverbal, and it starts very simple, and it gets more involved as you progress. That, to me, is what I'm designing," Blow says. "It comes by way of these puzzle scenarios, but it's really the communication that's the beautiful part."

The Witness is a big game. Blow says he thinks of Braid, which had around 70 individual puzzles, as a five-hour game. The Witness has more than 650, and he estimates will take many players more than 100 hours to complete it. But it could have been much bigger. The cutting room floor is strewn with ideas cut from The Witness. Some lacked sufficient depth to fully explore. Others felt ugly to play. Maybe Blow had the beginning of an idea, but wasn't the right person to make it a great puzzle. He explored hundreds of puzzles that simply weren't good enough to include.

That stands in contrast to the tendency of open-world games, especially triple-A titles—an inclination to bulk up with as much content as possible. "For me, I'm always trying to respect the player's time, and give the player an experience that's intrinsically valuable," Blow says.

Jonathan Blow

But it's not just the huge number of puzzles that led to the game's six-year development. A large portion of time was spent building the game's engine, something Blow did largely on his own: "You don't want to hire a bunch of people to make models when you don't even have an engine."

Was a custom engine entirely necessary, though? Could The Witness have been built in, say, Unity? Unreal?

"The answer to that question changes depending on what year it is," Blow says. "When we started this, probably not, but now those engines are more capable."

Blow is notoriously (and self-descriptively) meticulous, and building his own technology gave him full control over every aspect of how the game would look and feel. But the answer is more complicated than an engine's capability.

"I'm working very hard to make games that will stand the test of time," Blow says. "Games that, 20 years from now, if someone asks what are the great things to play, maybe this will be one of them. For that to be true, first of all you have to do a really good job designing and building the thing, but then secondly, you need to have enough control over your ability to provide the thing to people. I want to make sure that these things are available to people in the future."