The game created 100% by AI already has a playable demo. Codex Mortis tests the limits of game development!

Calendar 12/12/2025

Codex Mortis is being promoted as a game created 100% by AI. A playable demo is now available on Steam, showing how far generative tools have progressed in modern game development.

The phrase “a game created 100% by AI” sounds like a marketing clickbait, but Codex Mortis is genuinely attempting to push the boundaries of what we consider traditional game development today. The team behind the project has just released a playable demo on Steam, openly declaring that the entire production process – from graphics, through design, to implementation – was carried out solely using tools based on artificial intelligence. Sounds controversial? Because that’s exactly how it’s meant to be.

100% AI-driven development, no pretending

Press materials sent out by someone signing as Darek Crunchfest leave no doubt: Codex Mortis does not try to hide its lineage. On the contrary – the description on Steam explicitly emphasises “100% AI-driven development”, and the trailer is full of characteristic generative artefacts that are immediately recognisable to the trained eye. This is not a project that wants to "pretend" to be a classic indie production. It is a demonstration of the thesis: can AI now create a complete, playable game.

What exactly is Codex Mortis?

In terms of gameplay, Codex Mortis fits into the currently popular trend of roguelike arenas:

  • combining five schools of dark magic

  • creating and developing a dead army

  • fighting waves of demonic opponents

  • exploring the map in search of ancient pages of the book

  • time pressure, as an immortal boss constantly looms over the player

Mechanically, comparisons to Vampire Survivors are obvious, but the atmosphere is definitely heavier, darker, and oriented towards cooperation.

Demo now available, and this is just the beginning

The most important thing: this is not just a concept or teaser. The Codex Mortis demo is now available on Steam and can be played normally. The developers are announcing further development of the project – importantly, also with full support for AI algorithms, without a “return” to the classic production pipeline.

Revolution or Curiosity?

Is Codex Mortis the future of the gaming industry? It is definitely too early to answer that question. But one thing is certain: it is one of the first cases where AI is not just a supporting tool, but the central creator of the entire project.

If the next versions of the game show real progress, we may be witnessing the beginning of a very uncomfortable discussion for the entire industry. Because if "100% AI" can deliver a playable demo already today, the question is not whether, but when this technology will start to genuinely compete with traditional game development.

Katarzyna Petru Avatar
Katarzyna Petru

Journalist, reviewer, and columnist for the "ChooseTV" portal