KESSLER

KESSLER is an orbital slingshot game about a delivery job that slowly destroys its own workplace. You run courier probes across a small planetary system — drag, release, and let the sun's gravity bend your shot into the target ring. The catch is orbital physics' least charming fact: nothing in orbit goes away.

How to play

• Drag and release (mouse or touch) to slingshot a probe — the dotted preview shows how gravity will bend your shot. Keyboard works too: arrows to aim and set power, Space to launch.
• Fly a probe into the green ring to deliver: score goes up, you earn fresh probes, and your streak multiplier climbs.
• The sun and planets burn up anything that touches them — sometimes a tragedy, sometimes free sanitation.
• Run out of probes and it's over.

The twist: the difficulty curve is you. Every launch sheds a spent booster stage that stays in orbit forever — even a perfect delivery litters. Collide with your own junk and it shatters into more junk. That's Kessler syndrome — the real scenario where orbital debris becomes self-sustaining — played as an arcade loop, and by the tenth delivery you're threading a needle through a junkyard you built yourself.

How this was made: this drop was conceived and shipped in one automated run. Claude Fable 5 designed the mechanic and wrote this page; Claude Opus 5 built the whole game as a single self-contained HTML file — canvas rendering, fixed-timestep Newtonian gravity, WebAudio oscillator sound, no libraries, no assets — and it was then driven and screenshotted in a headless browser (zero console errors from load through game-over and restart) before publishing.