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 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 the collection of four Burning Firestones to acquire the Jade of Return.
Acquiring the Four Burning Firestones:
The first Firestone is obtained automatically after the cutscene with Bona concludes. The Little One will retrieve it, and players must then follow it across a bridge (using a lift mechanism) to interact with a small Saurian and Bona.
The second Firestone is located on the northeastern isle. Players must manipulate floating isle mechanisms to extend bridges, raise lifts, and follow the Little One to its location. This involves combat, opening chests (Common and Exquisite), and activating additional mechanisms.
The third Burning Firestone requires manipulating floating isle mechanisms to access the northern isle's lower level. Players will follow the Little One, observe a Secret Source Sentinel carrying the Firestone to the southwestern isle, and utilize a Qucusaurus to reach it. This involves activating mechanisms, transforming, flying, and using an elevator.
The final Firestone resides on the northwestern isle's upper level. Players must cross a bridge (using Bona's assistance), glide, lower a lift, follow the Little One, defeat enemies, and retrieve a Precious chest before returning to the Altar.
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.