6 epic things built with Claude Fable 5.2 (horizontal)

Claude Fable 5.2 is Anthropic's newest top-tier model, and the builds people are sharing show what it can do when you give it a large task. Felix Rieseberg at Anthropic gave it one prompt and no feedback, and eight hours later it had produced a full first-person shooter, with every 3D model, sound and texture generated from scratch.

The pattern across these projects comes down to three changes. It keeps working for hours or days without you, it splits big jobs across thousands of agents like a manager handing out tasks, and it checks its own work. In one case, 1,000 Fable agents formalized Fermat's Last Theorem in 30 hours, where Anthropic's first run with an earlier Claude took 11 days.

The catch is cost. Fable runs $8 per million input tokens and $40 per million output tokens, and on the Pro plan it can use up to half your weekly limit. Anthropic's advice is to start with Opus 5.5 and move up to Fable for the biggest jobs.

What's one project your team has shelved because it was too big to start? Tell us in the comments, and we'll be sharing more builds at AI Lounge.

Clips: Felix Rieseberg, Matt Shumer and Ethan Mollick on X, and Anthropic's launch page.