What is a community? At a glance, it's a group of people who interact and are connected to each other, but it's more than that. Look at any gaming message board. Skimming through the different threads won't tell you much initially other than the fact that everyone there has an interest in games. But dig deeper, and you'll find artistic people who create fan art or even fan fiction of their favorite series. And you'll witness people building relationships on these works and discussions based on simple shared interest, admiration, or even scorn and hostility. What this says about free will, creativity, and interaction is exactly what The Road to Gehenna explores, at least when it isn't giving you more puzzle rooms to solve apropos of nothing.
But why wouldn't it? From the first bit of downloadable content for the excellent Talos Principle, you'd expect more of the same brain-busting puzzles that the first game excelled at providing, and Road to Gehenna doesn't disappoint. The structure of The Talos Principle's puzzle rooms allows for a multitude of different configurations of light beams, refractors, switches, boxes, and recorders (which luckily are used sparingly here because any puzzle that used them tended to break your brain three times before you figured it out), so you'll still be spending days trying to think your way out of a seemingly-impossible mechanism. Don't go in expecting a ton of new ideas, though. You're not going to get any new tools or things to interact with. You'll occasionally run into puzzles that use these old ideas in new ways, but for the most part, you're just going to get a new set of expertly designed puzzles that are as good as anything the base game threw at you.
Much like its older sibling, the real heart of Road to Gehenna lies in the many terminals scattered across the game world. But while The Talos Principle was concerned with history and philosophy, Gehenna is a meditation on creativity and community. Instead of delving into a virtual Library of Alexandria and debating with a metaphorical serpent about the nature of free will, you'll spend your time examining the works of the programs forsaken and imprisoned by the system. As a sort of tradeoff for being put in prison, they're also cut off from the god figure program Elohim's care and influence, a parallel to the biblical stories of Hell as well as the Platonic ideal for a society that casts artists out. Using this as a strength instead of a punishment, they form Gehenna, a message board for the free exchange of ideas and creative works. Though they're trapped in their cells with nothing but a terminal to keep them occupied, Gehenna allows them to expand their worlds through the power of imagination and communication.
From the get go, you're free to poke around in all the different threads the programs have created, which feature ruminations on the nature of humanity, artwork, written fiction, and even simple text-based video games. The works themselves aren't as important as their creators. As you experience what these beings have created and how they talk to each other, you'll begin to see what roles they fill and how they relate to others. One seems preoccupied with studying human behavior, for instance, by researching human history and performing experiments on fellow posters. Artists of all different levels of sophistication post their works, from the quietly profound to the ridiculously pulp. And even the posters who don't actively create things participate through commentary and helping to promote other people's work. Admirers of specific creators spring up, and subtle relationships form based on this admiration. It's these posters and what they bring to Gehenna that bring it to life.
What's vital to Road to Gehenna's narrative is that, unlike The Talos Principle, which made you examine your very nature, you're not central to the experience in the slightest. Sure, the in-game conceit for you even trying to take down these puzzle rooms is that you're Uriel, Elohim's messenger, tasked with freeing everyone he regrettably incarcerated before the simulated world ends. But though you do free posters and evacuate them from the garden, the real crux of Gehenna is the posters themselves, how the threads evolve and change, how the moderation staff's goals shape and conflict with those of the other posters. In essence, you're just an observer bearing witness to what kind of creature the community has become. Even so, you'll find it thrilling getting to know everyone in the community through their passions, thoughts, and works. There's even a Reddit-style upvote-like system designed to encourage quality posting, though not everyone is happy with it. Road to Gehenna simulates community dynamics extremely well.
What doesn't work is the fact that the disparate parts of puzzles and message board threads don't really have anything to do with each other. In The Talos Principle, Elohim tasked you with collecting tetrominoes from puzzle rooms to attain enlightenment. Meanwhile, you the player are left wondering what the point of doing the puzzles really is, which feeds right into the discussions of free will and purpose with the serpent. With Gehenna, everything important is in the terminal segments. Without the questioning acting as a bridge to the game's themes, the puzzles are drained of all meaning and merely serve as more content to sell you. Luckily, the Gehenna bits are really strong by themselves, questioning what constitutes humanity by looking at the things they create and attempting to create things in the same way. But you can't help but think that Road to Gehenna would have been a much better, more focused game had it been a text adventure instead of one shoehorned into a 3D environmental puzzle game.
It's difficult to complain too much, though, when you're given more of the same kind of fantastically devious puzzle design found in The Talos Principle. You're going to be banging your head against a wall as you spend days trying to figure out how to get through that one room, finally feeling a tidal wave of elation and cleverness when you solve it. And you're going to enjoy getting to know the denizens of Gehenna as you ponder what of human nature is hidden in its art. It's a shame that these two excellent pieces never truly gel into something even more excellent, but even so, both still make for an enthralling, thoughtful experience together.