For a young man who majored in urban planning, entering the game industry was driven by a single, simple resolution: "Let's do what I love." He began his career as a level designer at Redduck, followed by stints at Nexon GT and NCSoft, before joining Nexon Korea. Over the years, he has contributed to game development from various perspectives, starting with level design and moving into system design and development strategy research.

He left the company early last year. The timing was perfect: his growing thirst for creating his own games converged with the realization that the AI technologies he had been studying were finally at a point where they could be practically applied.

The result is 'ASCII Survivors.' Combining the 'Vampire Survivors' genre with visuals composed entirely of ASCII characters, the game sounds like a nonsensical concept on paper. The monsters, bullets, and explosions are all text characters. It started from what he calls a "crazy idea": the notion that you could convey everything using only character codes.

Inven met with developer Kim Ju-seok near Jeongja Station in Seongnam on May 12. Our 70-minute conversation spanned his career, the specific ways he utilizes AI and its limitations, the complexities of the labeling debate, and survival strategies for indie developers. This isn't a tale of a successful indie developer's triumph; it is a candid account of leaving a major company to build and launch a game alone, and what he learned along the way.

Did your major in 'Urban Planning' help with 'Level Design'?

Could you start by introducing yourself and your career background?

"My name is Kim Ju-seok, and I currently operate as a sole proprietor under the name 'Indigo Vortex.' I have about 12 years of experience in the game industry. My first company was Redduck, where I started as a level designer. Afterward, I spent time at Nexon GT and NCSoft, and worked at Nexon Korea for quite a while.

Although I started in level design, I’ve participated in game development from various angles, including system design and development strategy research. I even served as an interviewer for job applicants at Nexon Korea for a time.

Later, I moved to Nexon Games briefly, but I eventually decided to venture out on my own to pursue more experiments and research. That sounds a bit pretentious now that I say it out loud (laughs), but that was the general flow of things.

You majored in urban planning, and I heard it was very helpful for game development. In what ways?

"Urban planning is a discipline that deals with space. When I was designing maps as a level designer, the instincts I developed during my studies naturally kicked in whenever I thought about how people perceive space or how they navigate through it. At the same time, there were moments while building maps where I realized how those concepts could be translated into a game environment. In a sense, I’ve learned how to apply the spatial knowledge I gained from the real world to game development through my experiences at various companies.

I think many people are unfamiliar with the role of a level designer. Even I don't fully grasp the exact concept. Could you explain it?

"In Korea, because we are so exposed to RPGs, there were even jokes like, "Is level design about designing how characters level up."

In games, a 'level' (sometimes referred to as a map, mission, or stage) refers to the entire space available for a player to complete their objectives. To elaborate, the term 'level' originally came from miniature games to describe terrain height, then expanded to the concept of dungeon depth, and eventually to abstract concepts like difficulty stages, finally becoming a general term for a unit of game space. In Korea, I think the term 'map design' was used more often than 'level design' in the past.

Ultimately, in one sentence, it is the job of designing the space itself based on 'what activities a player performs in a space and what experiences they gain through those activities.'

Given that level design experience is rare, you could likely join any other company. Why did you choose to go solo?

"I think I enjoyed the process of game development itself, experiencing various aspects of completing a game and even crossing over into commercial goal-oriented work. As I conducted personal research into AI, I couldn't help but think about deeply integrating it into the existing development process, and ultimately, I wanted to leave and pursue that research and challenge myself.

'ASCII Survivors' made with 'Godot Engine' and 'ASCII Code

"'ASCII Survivors,' which I recently launched on Steam, is a Vampire Survivors-style game where most of the visuals and expressions are composed of ASCII code. The entire screen is just flying characters. It’s a game where you survive in a space where you can barely tell which character is your own (laughs). I included a basic 10-minute survival mode, an endless mode, and challenge modes, and even the weapons and enemies are all made of ASCII code.

The idea came to me while I was playing and analyzing various 'Survivor-like' games on mobile and PC. At some point, I thought, 'Couldn't I do this with ASCII code?' I’ve always liked old roguelikes, so ASCII visuals came to mind naturally. When I looked, I realized there were no 'Survivor-like' games with ASCII visuals. So I thought, 'I want to experiment anyway, so let's just do it.' I started with that 'crazy idea' that I could show everything with just character codes (laughs).

Is there a specific reason you chose the Godot Engine for development?

"I’ve used Unreal Engine for most of my career. Since this was an early-stage, experimental project, I wanted to try something else. People in the open-source community have been saying for a while that "Godot is the future." One of the most famous recent games made in Godot is 'Slay the Spire 2.' With that in mind, and wanting to experiment with integrating AI into development, I chose Godot.

How was the Godot Engine after using it yourself, compared to Unreal.

"Asking me to rate it might be sensitive (laughs). Considering I’m someone who has primarily used Unreal, I’d give it a 80-90 out of 100. Its strengths are clear. It felt lightweight when I was studying it, and once I started using it in earnest, I found development to be much lighter and more agile than I expected. I think it’s a fantastic engine, especially for 2D games. Being open-source, access to plugins and source code is free, and the engine code itself is clear, making it great to dive into.

The downside is that references are still somewhat lacking. There were many times when I couldn't find answers and had to dig through the code myself. While it has some shortcomings in 3D compared to Unreal, it’s not impossible to use. Overall, I think it’s an engine with plenty of room for growth, and if you’re a beginner, it’s definitely worth considering as an option.

Do you plan to continue using the Godot Engine?

"For those who want to keep making 2D games or want to create games lightly, I think Godot is a sufficiently good option. My perception of Godot has improved significantly through this experience, and there is a high possibility I will use it again.

AI and Game Development - Utilization, Limitations, and the Labeling Debate

You mentioned you left after seeing the advancement of AI. How did you actually utilize AI in this development?

"I’ve been studying artificial neural networks consistently since they started gaining traction. I felt it had reached a level where I could consider not just using AI within the game, but integrating it into the game development process itself.

The core benefit this time was increasing development speed and the efficiency of iteration. It was also incredibly helpful in quickly testing various hypotheses and establishing new ones while designing the gameplay.

A concrete example is sound work. Since the game has terminal visuals, I thought 8-bit sound would fit well. I built a tool myself using AI that could simulate the type of 8-bit sound I wanted. I used that tool to create the base sounds, then edited them to refine the mood. I loved that I could build the exact type of tool I needed.

Are there any negative aspects or things you felt you needed to be careful about while using AI?

"Ultimately, game content must deliver fun and experience. If you leave that entirely to AI, you end up with a result generated without any creator's intent or direction. So, I thought the most important thing was to first design "what not to leave to AI." It is the creator's job to design the overall experience: what I want to show people, what kind of fun I want to provide, and how I will handle the decision-making process.

From that perspective, the ability to design game rules, optimize gameplay, and make technical judgments is an area that has become even more important in the AI era. No matter how good AI is, it must be backed by experience and technical judgment. Also, since there are very diverse views on using AI in resource production, that was something I thought about a lot while developing.

Regarding the sound work, didn't the fact that you used an AI-made tool lead to labeling issues? I heard you actually disclosed it on the store page.

"That's right. Ultimately, I was the one who made the tool, adjusted it, and edited the results, but I knew some people might perceive it as "AI-generated" because I used an AI-made tool. It’s a very sensitive topic, but I decided to be transparent and stated on the store page, "Some sounds were created using AI-assisted tools." I didn't see any reason to hide it or pretend otherwise from the start.

I think there's ambiguity in labeling something as 'made with AI.' There's no room for disagreement when using AI output as-is. But if I modified that result by 10%, or 20%, or even almost entirely, is it still 'made with AI'? Could you share more of your thoughts on this labeling issue?

"Steam is currently encouraging developers to disclose AI usage, and for now, we are following the policy guidelines of various governments and platforms. I had an experience that showed me how AI is perceived. I sent a message to a moderator on a Reddit channel to see if I could promote my game, saying, "I didn't use generative AI, but I used AI to build a tool to create sound assets. Do you consider this AI content?" They drew a hard line, saying, "If AI was involved in any way, it doesn't fit our channel." I realized that even if you don't use generative AI directly, people are drawing very clear lines regarding AI.

Ultimately, this issue comes down to how the consumer perceives it. Some users are fine with AI usage if the quality is good, while others don't want it involved at all. It’s a very difficult area to draw a sharp line.

What are your thoughts on the view that AI threatens the jobs of game developers? How much fear do developers actually feel?

"I can't easily speak for everyone, but it’s not unreasonable to feel fear. AI is a tool, but it’s a tool that threatens the very people using it.

Consumers have sharp instincts; they clearly distinguish between cases where they feel, "Did AI just slap this together?" and cases where they think, "This is AI, but it's really well-made!" or even, "Wait, this was AI?" I feel that the fear of losing jobs to AI is intertwined with fundamental concerns about how to make a living in the future.

I also find myself thinking about various things when I get help from AI to collect data. I assume developers have similar concerns?

"Exactly, the sentiment is similar. It’s hard to say what's right or wrong because, on one hand, it increases productivity, so why not use it? On the other hand, there's the view that productivity isn't the issue—it's that it's taking away jobs.

It’s very difficult for me to predict whether this is positive or negative. People working in companies are having various experiences depending on their company's stance, and since job postings now mention AI, it’s not unreasonable for game developers to feel that "AI is taking our jobs."

AAA or Indie - Industry Polarization and Indie Survival Strategies

There is an analysis that the game industry is polarizing into AAA blockbusters or indie games. As an industry insider and indie developer, how do you see this phenomenon?

"Since there is a clear consumer demand for quality and scale, the axis of large-scale game development will continue to exist. At the same time, as development accessibility improves and channels to promote games diversify, the increase in indie and small-scale development is a natural result. However, I don't think mid-sized games have disappeared; rather, the environment has changed so that small groups can now create what used to be mid-sized games, blurring the lines with indie development.

Ultimately, if you're making a game for commercial purposes, you can't ignore costs. Marketing is structured so that the more you invest, the deeper and wider the reach. No matter how well you use AI, there are limits. As a result, indie games are forced to polarize: either sharpen their focus so much that fans form a community around it, or create large-scale games that claim to have 'everything for everyone.

Another important thing is that forming a fan-based development community in advance has become a survival strategy for indies. It’s about building a consensus beforehand, like, "If it's a game made by that developer, I'll play it." Since simple festival or Indie Pass participation costs money, saving those costs while building a fandom is becoming a key strategy.

Are you saying it ultimately depends on consumer choice?

"That is highly likely. No matter how good a game is, it only has value if it reaches someone, and the process of reaching them costs money. This is the so-called marketing domain, and the more large-scale capital is involved, the wider the channels it can reach. Consequently, companies stuck in the middle find it difficult to recover costs, and the cost of promotion is higher than in the past. It’s a structure that inevitably leads to polarization.

I do see it as a positive change that platforms where you can play games lightly are emerging, slowly increasing the channels for small games to be discovered. I know there are places in Korea attempting similar things.

After Launching 'ASCII Survivors'

How long was the development period?

"The pure development period was about two months. To be precise, it was about 1.5 months, but there were various circumstances. Including the process of launching on Steam, it took about three months in total.

How satisfied are you after the launch?

"Honestly, this project was more of an experiment than a focus on sales or promotion. It was a process of verifying the things I thought about when I left: 'How can I integrate AI into development?' and 'How can I increase development speed while maintaining my direction?' From that perspective, I’m quite satisfied. It’s true that resource production speed was much faster than a typical game because of the ASCII visuals, and I spent much less time agonizing over things compared to the past. In that sense, I think I verified to some extent how to handle AI to increase speed while maintaining my direction.

Looking at the reactions from Steam curators and streamers, many were surprised by the lack of graphics but commented that "you can still feel the essential fun of a Survivor-like game" and "it has its own unique sense despite the ASCII visuals." Even if it doesn't sell a lot, confirming that people appreciate it when it's done properly, even with ASCII visuals, was meaningful. Honestly, I don't have any regrets that I should have added graphics if the environment allowed it (laughs), but the fact that I could try this experiment on my own meant a great deal to me.

Any words for those who might play the game after seeing this interview?

"If you buy and play it, I can only say I am incredibly grateful. I also hope that through this game, I can convey something to those who want to start solo development or those who think, 'Maybe I could do this too.' While making this game, I hoped that even though it’s ASCII visuals, I could leave a small impression on fans of Survivor-like games that 'there was this unique game.' Even if it didn't sell much (laughs), that feeling remains unchanged.

To Those Dreaming of Solo Development, and What's Next

Any tips for those dreaming of solo game development?

"In many cases, you can't help but dream of a big hit while making a game, but I think you shouldn't forget 'what you want to convey.' As development accessibility has improved, it might be easy to lose sight of the essence of making games. We live in an era where AI can make a game look plausible. But if you change your perspective, I think it’s an environment and opportunity to focus more deeply on what you want to convey than in the past. If we’ve reached a level where we can complete a game with ASCII visuals, it means we are now in a situation where we can spend more time and thought on 'what story I want to tell people' rather than worrying about the barriers of tools. I hope you can think of it that way. It’s a bit funny to be saying this when my game hasn't even sold well (laughs).

Do you have plans for your next project?

"Of course, I have the thought that next time I should go with proper visuals, not ASCII. I’m already continuing a few experiments. What I felt was important in this project is that the environment has become one where I can completely break and experiment with the rules of a game. The fact that the speed of that experimentation has become very fast is the biggest change for me. I’m also in the middle of discussing various things about AI with game artists. Nothing is confirmed for what's next, but I am preparing in various ways.

Any final words?

"Although this project fell short of showing dramatic results, regardless of success or failure, I was able to conduct many experiments in the development process in a short time. I think it served as an opportunity to prepare more thoroughly for when I make the next game or do something else.

Also, I am personally continuing my research on AI models, and I don't think AI will dramatically replace creators. Someone will always use AI to maximize their creativity to express something. We are in a transition period itself. It’s an era where the speed of technological development is faster than ever, and the faster the speed, the greater the confusion, but I think this situation has become an opportunity for me to think more about what I will look toward in the future. Thank you for the great conversation.