AI Is Moving From Dev Tool To Game Creator
Generative AI has been quietly slipping into almost every part of modern game development. A recent Google survey suggests around 87 percent of game developers are using AI agents in some way, whether that is for scripting, prototyping, level design or even dialogue. But a new project called Codex Mortis takes that trend to an extreme.
Codex Mortis is a Vampire Survivors style bullet heaven game that aims to be a proof of concept for how far AI assisted development can go. Its creator, who goes by the username Crunchfest3, describes it as the worlds first fully playable game created 100 percent through AI.
That tagline is obviously a bit of marketing flair, but the project does show just how much of a modern PC game can be built with AI tools and a relatively lean technical stack.
How Codex Mortis Was Built Without A Traditional Engine
One of the most interesting parts of Codex Mortis is what it does not use. Instead of relying on a big commercial engine like Unity or Unreal, the developer decided to skip a traditional engine entirely.
Under the hood, Codex Mortis is written in pure TypeScript. Here is the basic tech stack the developer outlined:
- TypeScript as the main programming language
- PIXI.js for 2D rendering and graphics
- bitECS for the entity component system that drives gameplay objects
- Electron to package everything as a desktop application for PC
Instead of a visual editor and drag and drop tools, the entire thing was effectively hand assembled in code. What makes that notable for PC gamers and hobby developers is that most of the coding work was guided by AI.
The developer says the whole game was vibe coded with Claude Code, mainly using Opus 4.1 and 4.5 models. That means they were feeding ideas, systems and problems into an AI coding assistant and iterating quickly based on the generated output. In their own description it was more involved than just typing make me a game and pressing enter, but the heavy lifting of structuring systems and writing a lot of boilerplate code was handled or accelerated by AI.
The content pipeline is also AI heavy. The art for Codex Mortis was generated using ChatGPTs image capabilities, while the animations were produced via a shader written with help from the same Claude based coding workflow. The result is a fully playable demo that runs like a typical desktop PC game, built in about three months with AI deeply embedded in almost every stage of development.
What The Game Looks And Feels Like
Codex Mortis is currently available in demo form on Steam. At a glance it sits firmly in the bullet heaven category popularised by Vampire Survivors and its many PC imitators. You navigate a character through dense waves of enemies, stack upgrades and try to survive progressively intense patterns of incoming projectiles.
Visually the game definitely carries what many players would instantly recognise as an AI generated vibe. The art style is muddy and indistinct, lacking some of the sharp visual identity that hand crafted pixel art or carefully directed 3D usually brings. Outside of that slightly uncanny presentation, the core loop seems familiar to fans of the genre: you move, you dodge, abilities trigger automatically, and you chase that satisfying escalation of chaos on screen.
Even if the art style is not to everyones taste, the important point is that Codex Mortis functions like a normal PC game. You have input handling, rendering, enemy waves and systems for progression all stitched together into a coherent experience. For AI assisted development, that alone is a milestone. It suggests that with the right guidance and a good understanding of programming fundamentals, an individual developer can lean on AI to speed up or simplify a large portion of game creation.
The marketing leans into the controversy around AI in creative fields. The cinematic trailer, also AI generated, features a robed sorcerer obliterating a demon labeled AI antis, a deliberate poke at AI critics. Whether players find that clever or cringeworthy will depend on their stance toward generative tools in art and game design.
Is It Really The First Fully AI Created Game
The claim that Codex Mortis is the worlds first fully playable game created 100 percent through AI is difficult to verify. There have already been smaller experiments like Doomscroll, a browser game assembled using ChatGPT, and plenty of other hobby projects that push AI into every stage of the workflow.
What may differentiate Codex Mortis is scale and distribution. It is not just a toy prototype hidden on a personal site but a game releasing on Steam and potentially sold as a commercial product. That gives it more visibility to PC gamers and makes it part of the wider conversation about how AI will coexist with traditional game development.
For players, Codex Mortis is less about redefining genres and more about showcasing what current AI tools can produce when paired with a determined solo dev. For aspiring PC developers, it is a sign that the barrier to shipping something on Steam is getting lower if you are willing to learn some basic web tech like TypeScript and PIXI and then lean hard on AI to help with structure, art and iteration.
Whether vibe coded becomes a badge of honor or a warning label is up for debate. But Codex Mortis shows that AI is no longer just a background helper for small tasks. It is now capable of powering almost the entire pipeline of a playable PC game from code to art and that has big implications for the future of game creation on our rigs.
Original article and image: https://www.pcgamer.com/games/roguelike/this-roguelite-claims-to-have-the-dubious-honor-of-being-the-worlds-first-fully-playable-game-created-100-percent-through-ai-in-a-milestone-for-slop-everywhere/
