Developer Grolaf has released a demo for Codex Mortis, a bullet hell game styled after Vampire Survivors, claiming it as the world's first fully playable title created entirely through AI tools. The project, built over three months without a traditional game engine, uses AI for everything from code and assets to music and animations. While the demo garners mixed reviews, it sparks debate on AI's role in game development.
Overview
Codex Mortis invites players to wield death as a weapon in a necromantic bullet hell experience. The game lets users mix five schools of dark magic, create spell synergies, and command undead armies. It supports infinite builds and offers solo or co-op play, all developed 100% with AI assistance.
Development Process
Grolaf, also known as Crunchfest, spent three months on the project, starting with a prototype to test feasibility. No conventional game engine was involved; instead, the game runs on pure TypeScript. Rendering handles through PIXI.js, entity management via bitECS, and desktop packaging with Electron. AI tools drove the creation: ChatGPT generated artwork, Claude Code wrote animations via shaders, and the coding process relied on Claude's Opus models. Maintaining a consistent art style proved challenging, but the AI adapted across sessions. Animations simplified to shader-based effects due to technical hurdles, and Steam integration with Electron presented obstacles compared to Unity or Unreal.
Grolaf noted the approach was less mentally taxing than traditional methods, likening it to enhanced productivity.
Reception and Availability
The Steam demo, available for free, holds a 'Mixed' rating. Some reviewers appreciate its value at no cost, while forum discussions reveal backlash, with comments labeling it 'AI slop' and warning of industry risks. A few voices question the hostility toward AI in development. The full game awaits release, positioning Codex Mortis as a bold experiment in AI-driven creation.
