AI model Fable 5.2 builds a complete video game from a child's drawings

Blogger Lex reports that the AI model Claude Fable 5.2 built a complete video game from a single prompt, based on design documents drawn by his nephew Aiden. The result is a beat 'em up, a genre in which players fight waves of enemies while moving through levels, in the style of classic arcade games such as the Ninja Turtles titles and Streets of Rage. The author calls it a major milestone for what the technology can do, though that is his own assessment.

Where the idea came from

Aiden asked for a game for his birthday. His design included five selectable heroes based on family members, among them the family dog, Doggo, plus 12 bosses and a loose storyline. One objective was to rescue the family's puppy, Pudding. Lex shipped a first version in June 2026 using the Claude Code tool with the Opus 4.8 and Fable 5 models, but it held interest for only a couple of minutes and did not match the boy's vision.

What Fable 5.2 did

Lex got early access to Fable 5.2 and tried it on his most ambitious use case. One evening he gave the model the task of finishing the game, allowing it to use OpenAI's image generator and ElevenLabs' audio tools, and by morning the game was ready. The model discarded most of the earlier code and rewrote the game from scratch. It produced about 175 images and 140 audio clips and added cutscenes, smashable crates and an ending. According to the author, it also wrote a bot that played all 12 stages in a headless browser and checked the screenshots.

Playtesting and additions

Lex connected four PS4 controllers to his MacBook. Aiden said the game was exactly as he had imagined it. After playtests, special abilities were adjusted with Claude's help and more family members were added, including a grandmother, a grandfather and the pet turtles Goldie and Billy. The number of heroes grew from five to eighteen.

Resources used

The author lists about 600 Claude requests over two days, roughly 500 OpenAI images, and from ElevenLabs 11 music tracks, about 100 sound effects and 90 announcer lines. He puts the total at around 340 million tokens. The game can be played on the author's website.