What are we working on?

Devil’s Terminal is a mystery coming of age story about a loser teen plagued by a controlling voice. The story takes place at Guidance Spiritual Retreat, a camp that promises to exorcize the problem out of “problem children.” The MC (Main Character) meets four fellow troubled kids, the camp's shady owner, a lively counselor, a quirky medium, and an omniscient computer that promises to guide the MC out of their loserdom.

Soon (like 30 minutes in), it becomes obvious that the camp is not what it seems.

There was some sort of cult here…

The computer seems to accurately predict the future….

The five kids weren’t brought here by accident…

These are just a bunch of “objective” facts. We wanted the player to decide what those facts mean to them, because, in our opinion, facts never stay “objective” for long.

We made the MC have “filters”—lenses through which they experience the world. Much like in real life, perception shapes the MC’s understanding of reality. This means the challenge now wasn't just tracking what the MC knows, but also how that knowledge is interpreted. This makes our concept uniquely cool to us, and, unfortunately, a unique pain in the ass to write.

What is our goal?

The sweet spot between a gripping, guided narrative and an open-feeling structure is an elusive thing that many games never find. We want the best of both: tons of freedom, but every piece of content has to hit hard and feel relevant. We want the player to choose the experience they would want and then give it to them the way they want it.

Once we entered the active writing phase, it became clear that manually tracking the multitude of available facts was insanely hard. The MC keeps uncovering new clues; each clue can be interpreted differently depending on the MC's perspective; the reactions to the same clues can vary for each character; what the MC knows and believes constantly reshapes the paths available to them. Trying to manage all those branches manually wasn’t just impractical, it would also lead to a worse game overall.

This is where our attempt to design a new Detective System came in. It would help us curate the experience of each player while hiding the puppet strings behind the curtain. The system had three key goals:

Accounting for perspectives: The same fact will mean different things to different players. The same falling brick can be a result of a curse, an unfortunate accident, or even an attempted murder. We wanted the players to interpret things through different lenses—like skepticism or mysticism. It’s unsatisfying to tell a skeptic that they are up against supernatural demons, and for a mystic, it would suck to learn that their spells are stupid and don’t fit inside a realistic setting. So we let our player pick a lane and then make the story fit them, not the other way around.

Structuring the clues: We had to organize all the facts the MC gathers into Threads—groups of related clues or questions they’re curious about. Then we need to track which facts are known to which character at which point. Every one of those threads needs to fit into each possible theory. You can learn everything there is to know about a person, and then you can decide if what you’ve learned points to them being a lunatic or a prophet.

Making writing manageable: To keep the writers sane (in reality, it still makes ‘em crazy), we needed a system that would track all available story branches, what the MC has learned, how they decided to view it, and how the arcs of other characters were affected by those choices. When the MC learns something, the player decides how they will view it and who they will tell about it—all that needs to be tracked.

Now let’s look at one example of an “objective” fact and track its transformation throughout the plot. “What is the connection between the camp and the cult that used to be here?” This seems like a good question to start with.

Accounting for perspectives

The MC’s perspectives: Players view facts through different lenses, which then shape the conclusions they draw. This adds flexibility and lets the players mold the story with their own spicy or minty takes. We call these perspectives Rails. The Rails are:

Structuring the clues

Threads: The clues are split into thematic Threads, each representing a bigger question or idea swirling in the MC’s head. These Threads aren’t just storylines—they’re the backbone that keeps the whole game together.

Sparks: Inside each Thread, there are separate strings of interrelated facts, which we call Sparks. Every new discovery doesn’t just add to the mystery—it builds on what the MC already knows.

The state machine: The Sparks stack into one logical chain. If the MC uncovers Spark #3, they automatically know Sparks #1 and #2, simulating a natural flow of understanding. Clustering Sparks into Threads gives us a way to manage the player’s knowledge and easily navigate the information in a data matrix manner.

We took massive inspiration from the Sorcery!’s state machine as it was described in Jon Ingold’s lecture for GDC.

Making writing manageable

We’ve laid out the entire story on a map that not only tracks the main plotline but also every branch that can be made available by the player’s choices. This lets us visualize both the chronology and the pacing and gives us a bird’s-eye view of how the game unfolds.

Mapping out the plot structure allows us to know:

With everything mapped out, we were finally able to break up the massive writing workload into manageable tasks. Each task now lives on a task board, and seeing those “Done” statuses pop up is now what we all live and die for.

What do you think?

We’re still constantly tweaking the system, but, after mapping out everything, we think this new approach will let players have a voice in how the story plays out. We really appreciate when game developers consider the meta level of their own medium, so we decided to approach the “choice” side of “player choice” from that meta perspective and figure out a new way to use the player’s decision making process to shape the game’s story. If you have thoughts about what we’re doing, any advice for us, or just an interest in talking about games we would love to see you on our Discord!

Discord link: https://discord.gg/chJd8HHQXw

Authors:

Mato, director of Devil’s Terminal

Lev Gorodetskii, narrative designer of Devil’s Terminal