Underwater Nocturne is the second quest under the Canticles of Harmony Quest quest chain in the Faded Castle for Genshin Impact 4.6. See how to unlock the World Quest, its walkthrough, and the complete rewards here in this guide!

How to Unlock Underwater Nocturne

Complete The Shadow Over Petrichor Quest

To unlock Underwater Nocturne, you must have completed the previous subquest of Canticles of Harmony Quest, The Shadow Over Petrichor!

The Shadow Over Petrichor Quest

Underwater Nocturne Walkthrough

Continue exploring the Faded Castle

Continue exploring the Faded Castle by going upstairs, and following Osse. Upstairs, you can either go to the room where a Teleport Waypoint lies, or go right and follow Osse to the stage to trigger a cutscene.

Note the going to the stage will eventually lead you to the room to the left where a Teleport Waypoint is located.

Take the Blank Score

Talk to Osse on the stage and play through the cutscene. Osse will ask you to Take the Blank Score by solving the Autoharmonic Reed Pipes puzzle. You can find it on the room where you can find a Teleport Waypoint.

How to Take the Blank Score

	Puzzle Solution
1	Go to the right Autoharmonic Reed Pipe and play a tune to adjust it. Move it one level only to match the indicated note near its back.
2	Head to the left Autoharmonic Reed Pipe and do the same thing as the first one. Move the arrow to the middle part to match the note near it.
3	The pedestal containing the Blank Score will be unlocked, along with an Exquisite Chest, after solving the Autoharmonic Reed Pipe puzzle. Grab the Blank Score and return to the stage to progress.

Play the Symphony on the Mural

Go back to the stage and put the Blank Score onto the pedestal to play the Symphony on the mural. It will trigger a cutscene where Boethius will come out from the mural.

It will also activate the stage and you will be able to interact with it later to get a Luxurious Chest, and retrieve the Tuba Mirum score!

Osse Becomes Monsieur Os

After talking to Boethius in the cutscene, Osse will become Monsieur Os, with a title "Cassiodor" underneath. You should be able to pet Osse without him getting mad now after this part!

Defeat the Golems

After the cutscene with Boethisus, he will wake up four Golems to attack you. You can easily beat them if you have a Geo Character, like Zhongli or Arataki Itto, as they can tear through their shield quickly.

The quest will end after defeating the statues and after a cutscene. You can also head back to the Harp, and begin the performance on the mural to get the Tuba Mirum Score!

Tuba Mirum Location and How to Use

Underwater Nocturne Information

Sub-Quest of Canticles of Harmony Quest

Underwater Nocturne is a subquest of the Canticles of Harmony quest, where you try to help the people in Remuria and uncover the strange things happening to them.

Underwater Nocturne is the Second part of the Canticles of Harmony Quest world quest chain.

Canticles of Harmony World Quest Guide

Underwater Nocturne Rewards

Total Quest Rewards

Total Quest Rewards
Primogem x20	Mora x32500	Hero's Wit x2

Genshin Impact Related Guides

All Quests and Quest Types

Other Canticles of Harmony Quest Guides

Canticles of Harmony Quest Line Guide

All Fontaine World Quests Guide

List of World Quests