Saltline

About this game

Saltline is a one-level first-person shooter that runs right in the browser. You are a Port Authority breach unit dropped into Saltline Terminal at dawn: the port's security net has gone feral, and you have to cut its three uplink relays and reach the boat while robot dogs and drones close in. Move with WASD, look and fire with the mouse, aim with the right button, reload with R, sprint with Shift, crouch with C and press E to cut a relay. Phones and tablets get on-screen touch controls.

Anthropic engineer Felix Rieseberg made it to test Claude Fable 5.2 with a single prompt and no human feedback, and shared it on 9 November 2026, the day the model launched. According to Felix, every surface, machine and sound is generated in the browser from code, nothing is downloaded, and the run took about 8 hours: roughly 2.7 million output tokens and 445 million input tokens (mostly cached), or about $550 at API prices.

The level is short (a few minutes for most players) and it is heavy: some players report stutters or a frozen tab on weaker machines, so lower the quality in Settings if that happens. It is hosted as a public Claude artifact.

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Felix Rieseberg

@felixrieseberg · Nov 9

I wanted to test Fable 5.2's quality with one-shot prompts without human feedback. Everything in this game is from scratch: models, sounds, textures. ~$550 at API pricing, ~2.7M output and 445M input tokens, heavily cached. Took 8 hours! Play it here: claude.ai/artifact/BGY1S…

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