In Genshin Impact, after assisting Bona in purifying the Abyssal Corruption from the Chu'ulel Light Core, players must help her locate the Primal of Flame. Once found, Travelers must present two Pyrophosphorites (obtained during the Palace of the Vision Serpent Quest) to the Altar of Primal of Flame.

This offering opens a path to Tonatiuh, a floating island above Ochkanatlan’s Cradle of Fleeting Dreams. Reaching Tonatiuh completes the To the Sky-Road Quest and begins The Other Side of the Sky Quest, requiring the collection of four Burning Firestones to acquire the Jade of Return.

Gathering the Four Burning Firestones in Genshin Impact

Burning Firestone #1

The first Burning Firestone is obtained as follows:

1. Arrive at Tonatiuh.
2. Wait for the cutscene with Bona to conclude; the Little One will retrieve the first Burning Firestone.
3. Follow the Little One to the bridge.
4. Activate the mechanism near the bridge to raise the lift.
5. Interact with the small Saurian.
6. Speak with Bona.
7. Watch the subsequent cutscene.

Burning Firestone #2

The second Burning Firestone is located on the northeastern isle. Follow these steps:

1. Rotate the right floating isle mechanism.
2. Rotate the left floating isle mechanism.
3. Proceed east across the extended bridge.
4. Raise the lift.
5. Follow the Little One to the second Burning Firestone.
6. Collect the Common chest along the path.
7. Activate the mechanism to the right of the Firestone.
8. Ascend the platforms to the upper level.
9. Defeat the enemy.
10. Collect the Exquisite chest atop the tower.
11. Activate the mechanism behind the chest to open the gate.
12. Descend to the small Saurian.
13. Open the locked door.
14. Tell the Little One, “Let’s return to the altar!”
15. Return to the Altar of Primal of Flame.

Burning Firestone #3

To acquire the third Burning Firestone:

1. Rotate the right floating isle mechanism.
2. Rotate the northern floating isle mechanism.
3. Cross the bridge to the lower level of the northern isle.
4. Follow the Little One.
5. Observe the Secret Source Sentinel carry the third Burning Firestone to the southwestern isle.
6. Move towards the northwestern edge.
7. Transform into a Qucusaurus.
8. Fly towards the Pyroculus.
9. Activate the mechanism within the tower.
10. Maintain your Qucusaurus form.
11. Fly to the unlocked door.
12. Activate the elevator to return to the upper level.
13. Interact with the small Saurian and follow it.
14. Activate the lift.
15. Proceed to the Altar of Primal of Flame.

Burning Firestone #4

The final Burning Firestone is on the upper level of the northwestern isle:

1. Cross the northwestern bridge.
2. Instruct Bona to tilt the bridge upwards.
3. Jump and glide to the upper level of the northern isle.
4. Lower the lift.
5. Follow the Little One.
6. Tell it, “Let’s return to the altar!”
7. Defeat the enemy (using a well-equipped team).
8. Again, instruct the Saurian to return to the Altar.
9. Collect the Precious chest.
10. Go to the Altar of Primal of Flame.

Presenting all four Burning Firestones to the Altar completes The Flowing Primal Flame Quest. A cutscene will then show the fire transforming the Jade of Return into a Golden Entreaty. The Dragon of the City of Flowing Ash will appear, prompting players to continue to the Nursery of Nightmares island to finish The Other Side of the Sky Quest and receive 50 Primogems.