Call of the Sea

(Chapter 3)

As far as I know, you could go directly to this puzzle after turning the power on. There are clues to find around the camps, but I didn't find all of them before solving. When you're ready to do the final puzzle, head around behind the ship and up the walkway. Follow this path until you reach a large hole in the ground. Activate the pedestal in front of the cliff and you'll see 7 symbols with paths on them. There are 6 "valves" located around this area. One behind you on the path leading up to the hole, 4 on the pillars left and right of the hole, and 1 on each side down the stairs. You'll need to open/close the valves in accordance with the picture posted below.

Lastly, turn the moon dial on the side of the hole to "new moon", which is the circle without any coloration. Then turn around and press the switch on the pedestal that you flipped earlier. This will open up the pathway to finish the chapter.

The journal with completed info for the puzzle:

During Chapter 3, you will need to play a stone organ to open a door.

TL;DR: You need to find the three frequencies, associate a number (diamond symbols) with each, use the tide key to match them to three different numbers and open those specific valves on the organ along with setting the dial to match the lunar cycle.


Longer explanation:

Before attempting this organ puzzle, you must have first solved the black ooze puzzle on the wrecked ship. Solving it will display 262-349-415, which are jotted down in your journal as three separate frequencies.

You then need to find what the associated number is with each of those frequencies using the small keyboard/piano in the far tent. That is its sole purpose. A note found in a case on the table will show which piano keys link to a diamond symbol, representing numbers 1-7.

Since you don’t know the frequencies of each of those symbol-linked notes, you’ll need to press all 7 of those keys. Norah will jot each frequency down in her journal, which contributes to chapter completion, but you could press only the 3 keys you need (if you got lucky and pressed the right ones).

Take note of the projector in here, you’ll need to reference this later. You then need to head to the stone organ to find the current tide level, which you can see by going down the steps on the right. It’s at one quarter (or a horizontal diamond at the lowest level that isn’t empty).

You then go back to the projector to check the slide for that tide level. This directly matches one number diamond with another, like a key or cypher. In this case, they match up like this (5 is horizontal, 6 is vertical and 7 is a cross):

1 → 5
2 → 6
3 → 7
4 → 1
5 → 3
6 → 2
7 → 4

Since matching up the frequencies with symbols using the piano, you know you need 1 (262 Hz), 4 (349 Hz) and 6 (415 Hz). Using the key above, these become 5, 1 & 2.

Whilst you’re in the tent, look at the calendar on the wall to see the lunar cycle. If you check your journal and the start of the log for this chapter, you can see the day is the 7th November 1934, which corresponds exactly to a new moon.

You now need to head to the organ one last time to tune it by opening the correct valves. These are dotted all around the organ, one being at the entrance and two others on each side down the steps. It’s clear that since it’s an organ you’re playing, an open valve means sliding the diamond up to unblock it, but a note near the organ will also tell you that.

Open valves 5, 1 and 2 and set the dial in the middle to new moon/black circle. You also need to make sure the other valves are closed. Then flip the panel at the back and press the lower button to activate the organ. The panel also shows routing of the black ooze, but I don’t really see how that helps with the puzzle.


Personal note: