In Genshin Impact, after assisting Bona in purifying the Abyssal Corruption from the Chu'ulel Light Core, players must help her find the Primal of Flame. Once located, Travelers must offer 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 Travelers to gather four Burning Firestones to acquire the Jade of Return.

Acquiring the Four Burning Firestones:

Burning Firestone #1

The first Burning Firestone is obtained automatically after the cutscene with Bona concludes. The Little One will retrieve it, and players must then follow it, activate a lift mechanism, and interact with the small Saurian before speaking to Bona and witnessing another cutscene.

Burning Firestone #2

The second Firestone is on the northeastern island. Players must manipulate floating island mechanisms, cross an extended bridge, raise a lift, and follow the Little One to its location. Along the way, they'll find a Common chest and, after activating a mechanism and defeating an enemy, an Exquisite chest. Finally, they unlock a door, ask the Little One to return to the altar, and do so.

Burning Firestone #3

To obtain the third Burning Firestone, rotate island mechanisms to access the northern island's lower level and follow the Little One. A Secret Source Sentinel will carry the Firestone to the southwestern isle. Players must then ride a Qucusaurus to a Pyroculus, activate a tower mechanism, fly to an unlocked door using the Qucusaurus, use an elevator, interact with the Saurian, activate a lift, and return to the Altar.

Burning Firestone #4

The final Burning Firestone is on the northwestern island's upper level. Players must cross a bridge (using Bona to adjust it), glide to the upper level, lower a lift, follow the Little One, defeat enemies, and return to the altar after retrieving a Precious chest.

Offering all four Firestones to the Altar completes The Flowing Primal Flame Quest, transforming the Jade of Return into a Golden Entreaty. The Dragon of the City of Flowing Ash then appears, leading players to the Nursery of Nightmares island to finish The Other Side of the Sky Quest and receive 50 Primogems.