Deep DarkHOW FAR DOWN CAN YOU GO?

Nobody has reached the bottom of this cave. Half of it is dry rock you climb down. The other half is flooded, and you have to dive through black water to reach the next dry cave. The deeper you go, the darker it gets, and the things that live down here get hungrier.

Scary: dark water, creepy sounds and monsters that jump out. Headphones make it better.

Click to look around with the mouse (or use the arrow keys). WASD walk and swim. Space jumps, or swims up. Shift swims down. C or Ctrl crouches to squeeze through low crawlways.
Some tunnels open into huge caverns with 8 tunnels to choose from. Only 3 go deeper (one is a hole in the floor); the others are dead ends hiding treasure. The high ones need the hook.
On land you breathe. Underwater your air runs out, so swim to the next dry cave fast. Glowing bubbles give you air.
Big falls, rocks, spikes and falling stalactites (listen for cracking!) cost health. First aid kits heal you.
Watch out for eels in the walls, and never swim toward a friendly-looking light in the dark water.
On a phone: the stick bottom-left moves, swipe anywhere to look, ▲ jumps or swims up, ▼ swims down (on land a tap crouches), USE uses the tool, tap a tool at the top to pick it.
Tools (1–4 or mouse wheel, click or F to use): ⛏️ pickaxe smashes rocks, digs through cave-ins and mines 💎 crystals · 🪓 axe cuts spider webs and fights monsters · 🔥 flares light the dark and scare the anglerfish · 🪝 hook pulls you to a wall.