Cthulhu: The Cosmic Abyss puts you in the shoes of Noah Williams, who is trying to find his colleague Elsa in the realm of the other world. On your way, you’ll have to solve many puzzles to unlock the path forward. You’ll also have to follow the trail of Andrew Marsh, who’s supposedly trying to awaken Cthulhu from his sleep and free him from his prison.
For more information on the game, please visit its official Steam page here.
Unlike other chapters, Chapter 4 doesn’t have a Corruption or Non-Corruption path. You will simply have to find a way to escape the otherworld and find the Star of Shamash.
Table of contents
The Other World
As you cross the portal to the other world, you’ll arrive in the same dimension where you encountered Mei. Keep going forward until you come across some Ocean-I gear.
Shortly ahead, you’ll encounter some human bones in the area. There’s also heavy fog here, and you can barely see a thing. Fortunately, you can use the Human Blood frequency from the sonar to find footprints covered in blood.
These footprints will guide you through the fog. At first, the footprints lead you to a small cave to the left. There’s Mei’s body here. It appears that someone has been taking care of it, likely Elsa.
Keep following the footsteps, and you’ll arrive at a temple-like structure. However, there’s a hole here. This hole is made up of Fluctuating Stones, a material that defies physics. You’ll have to drop into this hole.
Ocean-I Camp Near Chtulhu Statue
As you walk out of the structure, you’ll find yourself in front of an Ocean-I camp. There’s a Cthulhu statue here in the water, but it’s barely holding up with chains and could fall at any moment.
If you investigate the camp, you’ll find Andrew Marsh’s recording, as well as some minor clues here. You have to jump into the water, but the currents are so strong that they won’t let you get past and push you to another corner in the water.
Get out of the water from the hole where you’re pushed by the currents, and you’ll come out on top of the cliff in the same area. There’s also a voice recorder by Elsa Royer here. Now, once you’re here, use the Invasive Algae frequency to check out all the breakable platforms.
If you look down, there’s a platform connected to the chains that are supporting the statue. If you jump on this platform, the statue will be freed from the support and fall into the water, blocking the strong currents. You can then move ahead in the water.
The Deep Ones
If you progress more in the water, you’ll find a cave here made out of strange stones. This cave increases the corruption, and you won’t be able to go through it.
If you read the tablets around the entrance to this cave, it mentions that you need the scales of a Deep One to survive. Now, look around in the water, you’ll find a skeleton of the Deep One crushed under a slab.
Interact with the skull and analyze it. You’ll get the Deep One Bones frequency. Now, if you go out of the water, you’ll find some mummies hanging from chains. If you analyze them, you’ll get the Mummified Flesh frequency.
Now, you have to open the sonar and select the Deep One Bones and Mummified Flesh frequency. This will allow you to find a piece of the Deep Ones’ body that still has scales on it.
There’s a Mummified Deep One Arm that you can pick up among the pile of human bones. Once you’ve picked up the arm, you’ll be able to pass through the cave.
Keep going through the cave until you end up on the other side. Once you’re on the other side, keep going and ahead until you end up in front of a large structure.
Hall Of Whispers
If you look at the entrance of this structure, you’ll find out that it’s made up of Fluctuating Stones. Walk inside the hall until you reach a dead end.
After reaching the dead end, you’ll have to follow the path back to the entrance. However, when you reach the Fluctuating Stone at the entrance, you’ll find out that you’re high above the ground.
Go back inside, and this time, you’ll be teleported to the Gallery of the Fall. You’ll find some drawings on the walls here.
Gallery Of The Fall
As you enter the area, you’ll hear some whispers. There are four drawings here. Once you interact with each drawing, a disc featuring the drawing will pop out from the altar in front of the drawings.
You can throw the Deep One’s Arm now and pick up all four discs. If you go deeper into the hall, you’ll find a gate where you can put these four discs.
However, you’ll have to put the discs in this order from left to right: Dark R’lyeh, The Capture, The Slumber, The Awakening.
Once you do so, the walls on the sides will be removed, and you’ll be able to progress ahead.
The Crater
After passing through the Gallery of the Fall, you’ll arrive near the crater. There are some minor clues nearby. However, what you have to do here is to get down the mountain and get near those red lights that you see in the distance.
You’ll shortly find a broken Yith Teleportation device, as well as a researcher’s body nearby. You can’t progress ahead on foot here due to all the rocks and rubble.
Dive into the water, and that will allow you to get to the other side of the rocks. This entire area will be covered in heavy fog.
Here, you have to set your frequency to Yith Alloy, the same material the broken Yith Teleporter was made of. You’ll find some broken scepters in the area; you can’t pick them up, and you have no use for them.
However, if you maximize the range, you’ll find a scepter that’s intact. It’s hidden inside a cave, and you’ll have to crouch down to get to it. You can pick up this scepter and take it with you.
Once you’ve picked up the scepter, make your way toward the Yith Teleporter surrounded by red lights. Use the Yith Alloy frequency to find it.
After you get on the teleporter, thrust the scepter into the space. This will allow you to teleport to a new area.
This concludes the walkthrough for Chapter 4 of Cthulhu: The Cosmic Abyss.
Visit the game’s main hub here for more walkthroughs. If you’re looking for some other walkthrough hubs, please check below:
- Into Indie Games Homepage
- OPUS: Prism Peak – Walkthrough Hub
- MOUSE: P.I. For Hire – Walkthrough Hub
- All Will Fall – Walkthrough And Guides Hub
- Road To Vostok – Walkthrough And Guides Hub
Fahad Suleman is an avid fan of fighting games who spends most of his time writing walkthroughs and reviews for cozy indie titles or mashing around in Tekken. If he’s not writing or playing any games, you’ll often find him watching historical videos on YouTube for hours.
