Dragons could live between three and five thousand years, theoretically spanning an entire human civilization's Warm Age.
But in reality, there were no such long-lived dragons on Dragon Sleep Continent.
Since the establishment of the Holy Glint Empire, dragons had become prey to Snow Giants, with the vast majority ultimately falling on the Snowfields. And as the dragons fell, human dynasties also continually rose and declined.
Some of these dragons were hunted, while others sought death of their own volition.
The reason was simple: once dragons reached a certain age, they sought the elusive hope of returning to ancient times. But few succeeded; the majority ultimately perished on the journey back, maybe only those lost dragons mentioned in "Song of the Volcano" succeeded.
Becoming peculiar dragons born for vengeance, immortal and eternally existent.
Anyway.