Article · Simon Willison ·

Building a multiplayer game world with autonomous Fable-class models

Simon Willison

Simon Willison's blog post shares a piece by Jacob Sansbury describing how his company is building Spawn, a massively multiplayer gaming environment in which players use prompts to an in-game agent called Savi to modify the game world. Willison reports trying it on his phone and being able to prompt a castle into existence, then a dragon, then ride the dragon around the castle, calling the work an exploration of the bleeding edge of agentic engineering against frontier models.

Read at simonwillison.net The opening of the original, or for stories before 30 October 2026 an AI model's summary of it. Check the original before you rely on a detail.

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