Spiritus Sancti: Creating Voice-Controlled Horror Game

Introduction

Hi everyone, my name is Emmanouil, and I am 37 years old, living in Athens, Greece. How Divider Studios got started, huh? This takes us back quite a bit, to when Unreal Engine 4 was first released to the public. Up to that point, my entire experience with games was playing them. A lot.

One night, we were discussing game ideas with some friends, talking about how cool it would be if game X existed. A friend jokingly suggested, "Maybe you should make one". That was the spark that ignited the flame. I spent the next week thinking about that line. Why don't I make one? I went into research mode, found Unreal Engine, tutorials, documentation, and dove right in. I could not stop, it was all I was doing.

Right away, a friend and I started our first "studio" to try and make the next Alan Wake. Boy oh boy, did we bite off a lot more than we could chew. Eventually, we understood we were too green to even tackle something like that, so I transitioned into smaller projects and experimentation over the following years, learning the engine, pushing its limits, and seeing how far I could take it. I even built a working crypto trading bot inside Unreal Engine, which, surprisingly, actually worked. I never looked at development as a possible career until last year.

When I found out I was going to be a dad, I said to myself, "This is it". If there is a time to drop everything and try, it is now, before my daughter gets here and my time becomes even more limited. My wonderful fiancée agreed to support me in this endeavour. I gave myself 8 months to finish a game from start to finish, and to my surprise, I actually did it. Final Fall dropped 15 days before my daughter was born. I fell in love with every second of the process and realized that this is the career I want to pursue, it makes me happy. So Divider Studios was born right there and then.

Almost immediately after the release, I started looking for my next idea. I had been toying with voice recognition systems for a while and thought it would be really cool if voice could work as the core mechanic for an entire game, with proper recognition, not just a mic gimmick. I kept testing systems and accuracy for a long time until I got to a proof of concept that works. At that point, I knew I had something. Spiritus Sancti was officially in development.

As for the name Divider, that has been my username since I was a kid, and since this is a solo studio, I thought I would lean into it.

Key Inspirations & Unique Gameplay Mechanics

The initial inspiration was, of course, The Exorcist, the only horror movie that has actually gotten to me, ever. I wanted to create something that felt ritualistic and immersive, something that could give the player the same dread and horror I experienced watching that film. Fortunately, this is a very story-rich area in pop culture and real-life accounts across multiple religions, so research came back with plenty to work with. Using Latin as the default language for invocations also felt very right, though it had a bit of a learning curve for pronunciation.

I think this project is unique in a couple of areas. First and foremost, the voice recognition system. It does not just detect voice activity, it detects actual spoken language. Players will have to speak certain words, use timing and pronunciation to perform rituals, and interact with the environment.

Another thing that makes it unique, and I think Spiritus Sancti might actually be the first game to do this in the horror genre, is an opt-in feature for real-life contact. The game actively sends SMS messages to player phones at specific key moments of the game. This is entirely optional, but those who opt in are in for a treat. For the demo, I have also included the option for players to summon me to their stream in real-time by speaking an ecclesiastical invocation in-game. It has been going off around the clock since the demo launched, which means I am twice as tired as before, but totally worth it.

And last but not least, Cusco the dog. We might have another first here: this dog listens and reacts to your voice commands, so players have a very reactive companion that can also assist in certain areas of the game. Cusco started as a fun little prop, but players absolutely adored him, and I started redesigning some things around him to make him more involved. He now leads players to the current objective when asked to search. He was also named by a player who participated in a community post-event on X.

Story & Setting

We follow the story of Father Nathaniel, a newly ordained Catholic priest with little experience. One night, his mentor asks him to investigate a possible case of possession and verify it, but not engage. Nathaniel, being young and eager to prove himself, ignores the warning and engages in something much bigger than he is.

Players will get to experience a story about the consequences our actions and inactions can have on the human mind. We experience the result of Nathaniel's hubris and pride, as well as his regret. The story is not quite what it seems, and those who pay close attention will find there is more going on beneath the surface.

Horror fans, in general, I think, will like what this game has to offer, from the occasional jump scare to chase sequences, rituals, and the tension of having to speak while running for your life, which gives the experience a unique twist. Players should also expect to get stuck from time to time. Those who know me from my previous game know I have a deep love for hard puzzles. I tried to tone it down in Spiritus Sancti, but as the game progresses, new mechanics and difficulties are introduced, as well as more demanding lines to be spoken.

Art Direction & Development Tools

I have always been a fan of good, realistic graphics, so Unreal Engine is a clear choice. It has amazing out-of-the-box features that speed up the process a lot. For this project, besides the engine, the tools I used are Blender for modeling and some custom skeletons, Character Creator 4 and iClone for the main characters and their facial animations, Photoshop for the majority of custom textures, and, of course, Quixel Megascans and their amazing free asset library, which is an absolute godsend for indie developers.

After a certain point in the game, a new feature comes into play that I like to call the Veil. This lets the player actively split and remove colors from the environment, which really adds to the visual style in my opinion.

The idea for voice control actually started with Final Fall. There was a particular scene where I wanted the player to fight back against a hallucination, and every known mechanic felt wrong. I really wanted the player to be able to vocally say NO to the influence of the hallucinations, so the seed was there; it just needed watering. A lot of watering. I ended up using a QTE at the time, but the idea never left. When I got the proof of concept down, an entire game was designed around it.

Production Pipeline

It usually starts with a high-tech pen and paper and a lot of scribbling down ideas. I know how the game starts, how I want it to progress, and how I want it to end, but it is almost impossible to have every step locked from day one. There is a lot of adjusting and redesigning during development to better fit the story.

Solo developers take on a massive workload that would normally be spread across entire departments, and we mess around with software we have no idea how to use just to get something like a 3-second audio clip. What I find works for me is breaking massive tasks down into mini chunks that are chained to each other. Start with A because A is necessary for B, then move on to B, and so on. Controlled chaos, basically.

I have to mention that in recent years, AI has been a great help, but not in the way people might assume. I do not ask AI to give me code. I do not trust it for that, and I really dislike having to go through someone else's logic to understand how it works. What I do use it for is direction. If I want to build something I do not know how to build, I ask for a step-by-step guide. 90% of the time, it does not work, but it gets me close enough to understand how to do it myself. After a certain point, when you start creating advanced systems that interact with a lot of other things in the game, tutorials will not cut it anymore. They are incredibly useful when starting out, but custom systems are something you have to figure out yourself.

Incorporating Religious Themes

I was never a particularly religious person, even though I am Christian, but exorcism stories are something I heard as a child when I went on vacation to my village, and those stories stayed with me. When the core concept of the game was locked, I started researching actual rituals, stories, and first-hand accounts across the internet, mostly within the Catholic tradition. I think the rituals performed in Latin carry such great weight that they make you feel something even if you do not understand what was said. When a priest says Vade Retro Satana, you feel it, regardless of whether you know what it means.

The psychological aspects are directly tied to the supernatural, and I think they always have been. People are scared of things they do not understand, and absolutely terrified by things they kind of understand. The same reason zombies and monsters are so effective, they are almost human, but not quite. Some primitive part of our brain picks up that something is wrong and yells danger. Design one well, and the other follows naturally.

I will add that the demon at the center of the game is a real, documented entity with a legitimate Wikipedia page and references in various theological texts. I will not name it here. That is for the players to discover.

Character Development & Sacred Rites

The character models were created in Character Creator 4, but the characters themselves were created in my head during the nights I could not sleep. I kept imagining this woman, this poor, troubled woman tormented by demons, trying to hold on and in need of someone to save her, or at least try. That became Luisa. With the core concept in mind, I knew I wanted a priest, so Nathaniel came together pretty easily. I wanted him to be middle-aged but not yet broken or tired, just eager. Father Gabriel was a last-minute addition as a way to deliver some exposition and help to the player, and he ended up taking a very important role in the story. We might actually see him in person rather than just hearing his voice.

The sacred rites went through an interesting process. I pulled actual phrases from various sources and real exorcism accounts, specifically looking for lines that are short but pack a punch, because during active sequences, the player has to remember their lines under pressure. Giving them massive sentences would have killed the tension. Once I had a shortlist, I literally started speaking them out loud in the room, like I was exorcising the wall or something. The ones that felt good to say made it into the game. I am not going to lie, I felt kind of cool for a minute.

Changing environments are always a challenge. The more they change, the harder it becomes. But over the years, I have learned quite a few tricks, and the most important one is this: if the player does not see the transition happen, it never happened. I am a strong believer in the developer's golden rule: if it's stupid, but it works, it's not stupid.

To give a concrete example: there is a sequence in the game that looks like a hellish corridor covered entirely in spikes and tentacles. Those are just trees. Trees planted outside the corridor with their branches poking in. From the outside, it looks like a strange forest planted in a straight line. From the inside, it is limbo.

Development Progress

I think the most challenging design decisions are not technical in the sense of how do I make this door work, but how can I show the player what to do without showing them. It is a very fine line, and getting it right can make or break a game.

In my first project, that line was very blurry. I designed it the way I personally wanted to play it, and that thought never crosses your mind before you release your first game and actually watch people play it. That experience shifted my perspective entirely. Now, every system I design, I try to imagine it from the perspective of someone interacting with it for the first time. What if they press all the buttons at once? What if they spam inputs or never release them? Are the hints clear, or do they make the game too easy for what I am going for?

As for where things stand, the demo released about a month ago and has been getting solid organic traffic, which is great. The Summon the Developer feature is being used around the clock, which means I am awake almost always, but totally worth it. Overall, I would say the game is about 85 to 90 percent complete, and we are approaching the finish line pretty fast now that everything is in place. I am hoping for a summer release, but I do not want to announce a date I cannot stick to. Plus, we indie developers have to keep a close eye on when GTA 6 decides to drop.

Tips for Beginners

Honestly, in 2026, there is an abundance of information out there for pretty much everything imaginable. There are entire tutorial series on how to make a horror game that cover a lot of ground. But I think if someone wants to learn how to actually develop a game, and not just parrot someone else's tutorial, it is important they try to understand what those tutorials are actually doing.

Someone told you to create a struct with certain variables and a data table for your items. Try to understand how it works, because that has so many use cases beyond an inventory system. The general advice is: consume the knowledge behind the tutorial, not just the end result.

AI can also be a great help, and for beginners, even more so, because the simpler the request, the higher its accuracy tends to be. And lastly, other indie developers. We might not all know each other, but the majority of us feel like we are part of the same club. Even if our projects are in direct competition on Steam, we are never enemies. We are in the same boat, trying to make it, and that community is more valuable than most beginners realize.

Divider Studios, Indie Game Developer

Interview conducted by Stephanie Almogabar