Clues to the Sky
In this walkthrough for The Legend of Zelda: Tears of the Kingdom, we'll give you the complete tutorial for the main quest: Clues to the Sky Islands.
Following your discussion with Jiahto at Toto Lake, your goal is now to find the whereabouts of King Dorephan. Return to the Zora's Domain and head for the throne room. You'll see young Zoras playing and imitating King Dorefah. To find out the king's whereabouts, you'll have to spy on them. However, every time you approach them, they'll ask you to leave.
To be able to listen in, you'll have to go round the back and hide behind the throne. Approach slowly until you have the option of eavesdropping. You'll learn that there's a secret entrance hidden behind a cascade of clear water running somewhere between the Ploymous Mountain and the Zora's Domain.
To make sure you've made it to the waterfall mentioned, you'll find someone in front of the falls. Then climb to the top of the waterfalls and head to the left side. You'll see a hole you can jump into - this is where you'll find the Pristine Sanctum, where King Dorefah will be. To find the location of the secret entrance, take a look at the image below.
Once inside, speak with King Dorefah and tell him your discoveries. To be able to progress in the riddle discovered by Jiahto at Toto Lake, King Dorefah will give you 5 King's Scales.
Then head for Sidon to the Mipha Court at the top of the Ploymous Mountain to share your progress. To solve the celestial fish riddle, simply head for the fish-shaped island known as Floating Scales Island. This island is visible when you open the Great Sky Islands map.
To get to Floating Scales Island, simply climb up the visible waterfall, using the rocks that fall from the Great Sky Islands (using Recall to return to the top) or, alternatively, you can use a hot-air balloon. Indeed, you can find materials on the edge of the Mipha Court heading towards the waterfalls that come from Floating Scales Island. However, if you use a hot-air balloon, you must have a Flame Emitters Soneau artifact at your disposal.
Once on Floating Scales Island, destroy the wooden crates for arrows, as they'll come in handy soon, and wander around until the floating stones line up to form a drop. The coordinates of this location are: 4074, 0527, 0603.
Then shoot an arrow equipped with a King's Scale in the direction of the drop. This will cause a large jet of light to appear in the dam lake to the east of the Zora's Domain.
The Clues to the Sky main quest comes to an end, making way for your next main quest in Zelda: Tears of the Kingdom - The Water Temple.