This month, a small indie project called Codex Mortis emerged on Steam with a bold claim it might be the first fully playable game created entirely by artificial intelligence. While the idea of AI tools assisting developers isn’t new, Codex Mortis wears its AI heritage proudly, turning its development process into its central pitch and sparking conversations about the future of game creation. 

According to the Steam description of the game, Codex Mortis is a necromantic survival bullet hell with “roguelite” elements. Players dive into hordes of undead enemies, wield dark magic, concoct spell synergies, and strive to survive increasingly chaotic waves of foes. The demo available now on Steam, invites players to mix five schools of dark magic, raise armies of undead minions, and experiment with endless character builds either solo or in local co-op. The thematic emphasis on necromancy and destructive spell craft gives the game its unique flavor amidst its familiar gameplay loop.

The action unfolds in frenetic top-down combat that draws clear inspiration from indie hits like Vampire Survivors, blending fast-paced chaos with strategic builds and power combinations. 

What sets Codex Mortis apart and what has drawn the most attention is the developer’s claim that every element of the game was generated by AI. According to the game’s developer who goes by Crunchfest3 on Reddit they claimed that everything was slapped together with AI tools in just three months and that all the assets and animations were from GPT image and were a shader written by Claude Code. 

Some might see it as a landmark moment, a genuine experiment showing how far AI can take game development in a short period. From concept to playable demo reportedly took about three months, with no traditional engine or human created assets.

The current Steam entry for Codex Mortis is a demo, with the full game’s release date yet to be announced. Still, its existence has already become a talking point among gamers and developers that are curious about what AI game development truly means. Whether it ends up a beloved indie game or a quirky footnote in gaming history, Codex Mortis shows how experimentation can challenge assumptions about creativity and craftsmanship in the gaming industry.

As the landscape of game development continues to evolve, Codex Mortis stands as an early case study and perhaps a sign of more AI-generated worlds yet to come.