The exterior of the Shrine of the Coral Tomb differs from many others, being a rocky dome-shaped structure. Upon entering via a Siren Window to the West, you'll find yourself in a small entrance room with a waterfall flowing down to a pit. The main area of the Shrine is reached by jumping down to follow the water stream and spiralling down a system of water slides until you're finally spat out into the partially water-filled chamber at the bottom.
The tall central chamber is partially filled with water, although the level will increase higher as crews progress through the 3 puzzle stages. The cavity is plated with glowing coral and ancient structures, with a central stone ring under the water. Stone heads spout water to form 4 individual waterfalls pouring into the pool at the base. The water level must be raised 3 times by pulling 3 levers in a set order each time. Every time the water rises, a wave of Sirens will emerge to take on, as well as 3 more levers becoming accessible for the next stage to be completed. Once a correct lever has been activated, it will not be used again during the visit. When a lever is pulled a section of Who Shall Not Be Returning can be heard playing, with each correct lever pulled being the next section of the song.
Pieces of Coral Treasure as well as Siren Gems can be found at different intervals as the water rises, but the greatest stash of loot becomes accessible after the Shrine's water level has risen for the final time.
Journals
There are 5 journals scattered throughout the Shrine, written by Bel.
1. Seashell Earring
(Next to an Ammo Chest on the central underwater stone circle.)
I've come across many strange and interesting items in my time, but none more stranger and more interesting than the seashell earring. I found what I took to be a run-of-the-mill seashell in a rockpool that turned out to be an earring. How odd, I mused out loud, as I inspected it more closely. The sound of my voice triggered the earring and I heard the song of the merfolk, telling me to meet them. Which I did. They explained everything to me, and my eyes were opened to the world of possibilities that awaited me, deep beneath the ocean waves.
2. A Hidden Kingdom
(Down to the left of the yellow gem lever on the second puzzle.)
I knew of the merfolk, what pirate doesn't? But I knew nothing of their history or their culture. The earring gave me a glimpse into that world, and I wanted to see more. So I started to explore. I discovered Shrines and an entire underwater kingdom filled with a type of merfolk I had never seen before, who all seemed to be sleeping. Something about their kingdom told me I was glad they were asleep and as I went deeper, I started to discover the story of how they came to be. Although the new race of merfolk were created by the strength of one couple's love, this tale did not have a happy ending.
3. The Sea Queen and her Warrior
(On the right by an area of pink coral, just as you enter the North East cave.)
There was once an ancient Warrior who fell in love with a Sea Queen of the merfolk. Their love was all-consuming and neither could imagine life without each other. As time went by, they began to search for a way to bridge the gap between their two worlds. The Warrior met resistance from his people, but the merfolk possessed stones that could hold powerful magic and the Sea Queen believed it was these that would bring them together. The merfolk elders warned her that their kind was forbidden to use magic to turn humans into merfolk. But the warrior and the Sea Queen believed their love was strong enough to survive the consequences for breaking the sacred rules of her people. So she used a Mermaid Gem to turn him.
4. The Whispering Plague
(By a skull pile in a cave to the South by South West once the water level has been raised.)
Though the transformation was successful, it came at a terrible cost... it unleashed a curse that robbed the Queen and her court of their song. Now, a merfolk's song is so much more than a pretty tune. It is part of who they are, their soul and their collective memory. Without their song these merfolk became something else, something twisted and dark; the sleeping merfolk I had seen on my adventures. This new branch became known as the Sirens.
5. The Sunken Kingdom
(To the right of a Merfolk Statue on a raised area once the water level has been raised.)
As I've explored further into 'The Sunken Kingdom' (it's a great name, isn't it? I'm pretty pleased with myself, not going to lie) I've discovered more about the Sirens. Take this place, for example. I'm pretty sure it's some sort of tomb. The Sirens seem to have taken death, and honouring the dead, very seriously. The pool in the centre contains offerings to those who have passed, and there seem to have been a fair few of them. The Sirens were at war with everyone, the Ancients and the merfolk. The rage of the Queen filled all her kind, and they took every opportunity to inflict pain on others. Creating a kingdom from the ruins of anything they could drag down from the world above.
To save pirates from needing to take their new-found treasure all the way back up the surface, up to 20 loot pieces can be stored in friendly Mermaid Statues found along the way. Any Coral Treasure Chests filled with three loot items count as a single loot item, saving up space for the other Treasure items to be stored in the statues. Any Treasure left with the statues can be redeemed back on the surface from a friendly mermaid with a shell, emitting purple smoke. When interacted with, any treasure collected will float up to the surface and the mermaid depart.