The Moon-Bathed Deep is a new world quest that can be found on Watatsumi Island which was added with the 2.1 update. Divided into four parts, this quest is a bit lengthy. But you can finish it quickly as long as you follow this guide.
Activate the quest
To activate the quest, teleport to the Mouun Shrine on Watatsumi Island. Over there, you’ll find an NPC named Tsuyuko who is a shrine maiden.
Once you start talking to Tsuyuko, she will educate on an important legend about Watatsumi Island. Before making their home here, the people used to live in a place known as the Enkanomiya. They had no means to leave as there was a creature named the Dragonheir of the depths that was terrorising them. For a while, the people did their best to fight it off with the help of the Ooohirume no Omikoshi. However, they were only able to leave when the Omikami of the island, most likely Orobashi the serpent god, defeated the Dragonheir.
With the Dragonheir sealed away, the people left Enkanomiya and settled in Watatsumi Island.
Now Tsuyuko worries that since the connection between the two places has been broken, there’s a chance that the Dragonheir will be set free. To stop this from happening, the five seals, the Goshou Rocks, that maintain a barrier between Watatsumi and Enkanomiya need to be broken.
Eye of Watatsumi
To obtain the Eye of Watatsumi, teleport to Mouun Shrine and glide down from there.
You’ll find the first seal on a small island near the shrine. Once you get there, you’ll have to read the stone tablet beside the seal. While the words on it will relay the legend that Tsuyuko told you, it will also give you three directions: North, South and West.
Paimon will then suggest that you use elemental sight. When you do that, you’ll notice that the elemental energy is directing you in three different paths. You’ll have to follow these paths and break the orbs at the end with an Anemo attack. However, for every orb, you’ll have to fight a set of enemies ranging from Electro Slimes, Anemo Specters and Ruin Sentinels.
Once all the orbs are broken, the seal will be broken. Go back to it and pick up the small pearl inside of it. You now have the Eye of Watatsumi.
Fang of Watatsumi
To collect the next piece for the Quest, the Fang of Watatsumi, teleport to the Waypoint close to the Hydro Hypostasis. From there, using the navigation, search for the seal. You’ll have to be careful here since the area is full of enemies like Nobushi, Whopperflowers and Fatui Skirmishers.
Once you reach the seal, you’ll notice a Leyline Monolith in front of it along with a Thunder Sakura Bough. Ignore it for now and read the tablet next to the seal. Paimon will conclude that you need to protect something in order to break the seal.
Now, activate the Leyline Monolith and get ready to fight. During this timed challenge, enemies will come in waves, the first one comprising of Hilichurls. From then on, you’ll have to fight Mitachurls, Treasure Hoarders, Nobushi and Kairigi. All the enemies will be a bit tanky, however, if you use an Electrogranum while fighting, it will help take them down faster.
Once the enemies have been defeated, the seal will break and you can collect the pearl inside.
Fin of Watatsumi
The Fin of Watatsumi is also near the Hydro Hypostasis so teleport back to the same Waypoint. However, this time you’ll have to go in the opposite direction.
Over here, along with the seal are two platforms, both having a set of statues on them. One main statue to pray to and three fish statues. Like the previous seals, read the tablet and then, you’ll have to solve the fish statue puzzle.
The puzzle itself is rather straightforward. You have to rotate the fish statues until they are facing each other. When that is done, the platform beneath will begin to glow. Also, when you rotate the statue on the platform, the corresponding statue on the other platform will also move. Sometimes in the same direction and sometimes in the opposite
Solve the puzzle on one platform and then remember to pray to the main statue. That will lock the fish statues in place. If you don’t do this and move onto the next platform, the statues will move and your hard work will be for nothing.
Once both platforms are aglow, the seal will break and you’ll have the Fin of Watatsumi.
Tail of Watatsumi
The next piece for the quest is located on a small island off the coast of Bourou Village. As long as you follow the navigation, you should reach your destination without any problems.
Once you’re at the island, you’ll find two Fatui Skirmishers, Geochanter Bracer and Pyroslinger Bracer, in front of the seal. You’ll have to defeat them before you can read the tablet. When they’re out of the way, the next part of the quest is simple. Using an electrogranum, you need to light up the lamps around the seal.
A Thunder Sakura Bough can be found under a tree, right next to an Electro Cicin Mage that seems to be drawing on its power. It’s only after she’s defeated that the Thunder Sakura bough will be restored and you can summon an electrogranum.
Keep in mind that after you get the electrogranum, you have to move as fast as possible. The lamps have to be lit in one go. If the electrogranum runs out, you’ll have to start all over again. Thankfully, there is no particular pattern that you have to follow here so breaking the seal should be relatively easy.
Be ready for combat as soon as the seal breaks because three Fatui Skirmishers – Pyroslinger Bracer, Hydrogunner Legionnaire and Cryogunner Legionnaire – will appear. Defeat them and the pearl will be yours to take.
Heart of Watatsumi
Once you’ve collected all the pearls, teleport to the Sangonomiya Shrine and find Tsuyuko standing just outside.
As you talk to her, she will tell you that there’s one more step that needs to be finished which is unlocking the heart of Watatsumi. She will then ask you to accompany her.
From here, things get a bit tricky since the game’s navigation system isn’t really the best for certain quests, this one being one of them.
As you follow the navigation, it will lead you to a waterfall and indicate that you have to go down the waterfall to find the heart. If you do so, you’ll only get lost. The Heart of Watatsumi is locked inside of a cave that is located near the waterfall. The cave entrance will have a blue seal with the image of fish on it.
Input the four pearls and the barrier will disappear. The Heart of Watatsumi has been unlocked.
Key of the Moon-Bathed Deep
The final step of the quest is to obtain the Key of the Moon-Bathed Deep. To do so you’ll have to enter the Heart of Watatsumi. Inside, you’ll see one platform on which there will be a bowl of sorts. Around the platform, there are four fish statue puzzles and one of them seems to be broken as the light of the statues is very dim.
The way to solve the puzzle here is the same as before. Rotate the fish statues until they are facing one another. This time, however, as soon as the platform lights up, Hydro Mimics will appear and you will have to fight them. Make sure to pray to the main statue before you move onto the next puzzle.
Once you’ve solved the first three, you’ll arrive at the broken puzzle and notice that the fish statues cannot be rotated. They seem to be stuck. To get them to move again, instead of praying to the main statue at the end, pray to it at the beginning. A light will transmit from the statue and now the fish statues can be rotated.
The moment you solve the final puzzle, Hyro Mimics will appear as before. But this time, they will come in waves and you’ll have to keep fighting them until the final seal is broken. When that happens, a cutscene will begin and a key will drop from the orb of water on the ceiling and into the bowl below.
Collect the key and then speak to Tsuyuko. She will tell you that now that she has the key, Enkanomiya can be unlocked. But before she can do that, she needs to speak to the Divine Priestess, Kokomi first.
With this, you’ll unlock the achievement The Same Moonlight.