Climb down a deep, dark shaft with up to three friends. A blind worm grows out of the rock and hunts you by scent: move fast and it follows your trail. Light holds it back, but not for long. Hook, swing and rappel deeper, while your friends' voices echo down the shaft.

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Planned Release Date: Nov 26, 2026

This game plans to unlock in approximately 2 weeks

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About This Game

Go down. It's waiting.

Unknown Depths is a co-op horror descent for 1 to 4 players. Your team climbs down a vast, procedurally generated shaft, far too big and open for comfort, and something in the walls is waiting.

It hunts by scent

Move fast, by sprinting, swinging or falling, and you leave a trail of glowing dust behind you. After a quiet spell the rock near you shudders, cracks and something grows out of it. You'll hear it before it feeds: a rising, clicking rattle, jaws shuddering open and the dust starting to drift its way. Then it breathes in across the shaft, pulls your scent straight to it and follows the trail.

If it reaches you, you're gone.

Light is the only shelter

Lanterns, glowing fungus, crystals and shrines hold back the dark. Inside their light you leave no scent, and the worm can't breathe you in or grow into the light. So you dash from one pool of light to the next, and every dash leaves a trail. But light doesn't last. When the worm strikes a light, it gutters and goes out seconds later, and you have to move on.

One hook, one rope, a long way down

Every diver has a grappling hook on about 25 metres of rope. Catch a ledge, swing across the open shaft, rappel down sheer drops or haul yourself back up. Hook a teammate to pull them to safety, or rope yourselves together. Falls hurt, stamina runs out, and a swing into rock at the wrong speed can kill you before the worm does.

Voices in the dark

Proximity voice chat carries down the shaft. The further away your friends are, the more their voices echo off the rock, until they're gone. And when you die, you keep talking as a ghost.

Together, until you aren't

Death is instant. The dead watch the living, and kindling a shrine brings the whole team back. When nobody is left, the shaft rolls anew. Every run is a different descent.

Deeper down, it changes

Below the grey Stone Depths lies the Bloom: warm amber haze, root bridges and orange spore shrooms that feed on your movement. Feed one too much and it bursts, calling a worm straight to you.

Features

  • Online co-op for 1 to 4 players, with proximity voice chat that echoes down the shaft

  • A procedurally generated shaft that's different every run

  • Multiple biomes

  • A blind creature that grows out of the walls and hunts by scent, not sight

  • Physics-driven climbing, swinging and rappelling with a grappling hook

  • Many difficulties

  • PS1-style visuals: wobbling vertices, dithered colour and thick fog

Mature Content Description

The developers describe the content like this:

Unknown Depths is a horror game. Players are hunted by a large worm-like creature that bursts out of the cave walls, and being caught kills the player instantly. Expect a tense, dark atmosphere, sudden scares and loud creature sounds. Deaths are not very graphic.

System Requirements

    Minimum:
    • Requires a 64-bit processor and operating system
    • OS: Windows 10 64-bit
    • Processor: Intel Core i5-4460 or AMD Ryzen 3 1200 (quad-core)
    • Memory: 8 GB RAM
    • Graphics: NVIDIA GeForce GTX 960 2 GB or AMD Radeon RX 470, with DirectX 12 or Vulkan support
    • DirectX: Version 12
    • Network: Broadband Internet connection
    • Storage: 1 GB available space
    • Additional Notes: An Internet connection is required for online co-op.
    Recommended:
    • Requires a 64-bit processor and operating system