How to find King Dorephan.
When you get there, you’ll find that three Zora kids are playing a game there.
Stand outside the entrance of the Throne Room and look to your left.
You should see a waterfall/stream area here.
Climb into this and follow it around to the left, climbing carefully along the ledge when you oughta.
When you’re close enough to listen, a control prompt will appear.
In Zelda: Tears of the Kingdom, King Dorephan is in Pristine Sanctum.
This is east of Zora’s Domain and east of Mipha Court.
Now, this part takes a bit of Stamina.
you better swim through the waterfall.
Once you do, you’ll find a secret entrance to Pristine Sanctum on the other side.
If you have the Zora Armor, you could simply swim up this waterfall to get to Pristine Sanctum.
Then, use Ascend to pop up through the floor into Pristine Sanctum.
Once inside the Sanctum, you’ll find King Dorephan!