The dive
The current carries you. Buoyancy does the rest.
You never steer. You rise and sink with the controls a real diver has, and the cave asks for all of them at once.

BCD
Press + to add air to the wing and rise, − to vent it. Air swells as you climb, so vent on the way up.
Lungs
Drag up to breathe in and lift a little, down to breathe out and sink. The fine trim between puffs.
Ears
Going down squeezes your ears. Equalize when the ring fills, before it starts to hurt.
The score
Stay close to the line. Climb to ×5.
Every metre scores. Stay near the guideline to build up your multiplier; drift off and it slips. Touch rock and you are back to ×1.
- ×1Start
- ×215 m
- ×330 m
- ×445 m
- ×560 m

The cave
A new cave every dive. Today's is the same for everyone.
Each cave grows chamber by chamber and never ends. Six stages lead down from the Entrance to the Abyss, each tighter and deeper than the last. Once a day everyone dives the same cave: see who got furthest today.
- 1The Entrance5–7.5 m
- 2The Galleries6–13 m
- 3The Crawlways10–20 m
- 4The Narrows13–25 m
- 5The Deep16–30 m
- 6The Abyss19–35 m






A dive ends when the air runs out, you rise too fast, stay past the no-deco limit or hurt your ears. However it ends, every metre you swam still scores.

Learn
Learn it in open water first.
Four short lessons, each with its own control playing the skill out, and drills in open water to practise them before the cave asks for everything at once.