It takes me many days to find all these secret stone tablets. Hope it's helpful for you. English is not my first language, if there is any typo or any other thing can be improved, please let me know. Thanks.

This one is easy to find: just above our nest in the tree.

Fly to the glowing area on the tree

Land and interact

When you solve all the puzzles in the first shrine, you will finally enter the portal chamber. The secret stone tablet is beneath the portal and it's hidden where no one would notice. I will not admit that it takes me hours and hours to find this one 💢 It's recommended to get the white feather in front of the portal first.

After using the portal with 2 souls, you will be sent to a island.

Grab a weight.

Take it to the yellow switch:

Fly to the room across the river.

Get it! And don't forget to collect the white feather. ^_^


Edited on 2025 Nov 21
Bad news: AN RED APPLE CAN'T DO :P

This stone is not hard to find.

Once you have solved the last puzzle in the second shrine, cross the door and look upward. You will see the stone.

Go to the plank road.

You will see two switches.

Eyes to the door.

Fly to it and carry the weights to push the switchs.

The first one is done.

And then the secone one.

After finishing both switches, just fly to the room to meet the stone.

This stone is also in the portal chamber. When you enter the chamber, turn left, and follow the white soul, you will finally find the stone. it's not hard.
Turn Left.
The white soul guilds you.
Eyes left the glowing.

It's a little changing to meet this stone.

First, you have to complete a timed challenge of passing through all the rings.

My skill is
1. Try again when failed
2. Keep the crosshairs centered on the ring at all times
3. Keep croaking to collect the green souls so that you can keep flying fast

After you completing the challenge, find this ring on which there is a lighting-like ray. Follow the ray and you can find the entrance.
Oh, and a white feather is your bonus XD.

Like the 2rd stone, this one is hidden beneath the portal.