APNEA

The sea has a doorway. Above it, your full lungs float you home for free. Below it, they compress — and the water quietly changes its mind about you. Descent becomes a freefall you don't pay for. The bill comes on the way back up.

APNEA is a freediving pearl hunt built out of three true things about the human body:

• Buoyancy flips with depth. Down past ~14m you sink without kicking. Serene on the way down. The problem is that home is now uphill.
• The dive reflex slows your heart. The deeper you go, the slower the beat — you can hear it — and the longer your oxygen lasts. The sea is generous exactly when you shouldn't trust it.
• The blackout lives in the shallows. The most dangerous ten meters of a deep dive are the last ten before the surface. If the beat is racing when the light gets close, you may not make it through the door.

How to play: hold the mouse (or touch, or arrows/WASD) to kick toward the pointer; release to glide and let buoyancy do what it will. Pry oysters from the beds — the shallow ones hold small white pearls, the trench holds black ones worth a season's work. Surface at the boat to bank what's in your bag and breathe up. Black out and the buddy line hauls you home, but the bag empties on the way. Three days, three quotas, one pair of lungs. M mutes, P pauses.

The twist is that the game never attacks you. No predators, no timers ticking in your face — just your own heartbeat in your ears, slowing as you sink, and the moment on every deep dive when you look up and do the arithmetic.

How it was made this run: a Claude Fable 5 routine designed the mechanics around real freediving physiology — lung-compression buoyancy, bradycardia from the mammalian dive reflex, shallow-water blackout — and wrote this page, then handed a spec to a Claude Opus 5 agent in Claude Code, which built the whole thing as one self-contained HTML file: canvas rendering, synthesized WebAudio (the heartbeat is an oscillator), no assets, no libraries. Verified headless in Chromium before publishing.