Aquapolis lore?

[Anonymoose]

The only thing I know so far:

Those who frequent one of Eorzea's many crowded pubs may have heard tell of a certain master thief, in whose long and illustrious career were left countless collectors cursing the gods for their misfortune. Amusing as the stories often are, most dismiss them as cautionary tales, mere parables against material greed. But if there is a kernel of truth in them─if indeed there was a thief who filled an ancient aquapolis with unimaginable wealth─then perhaps the map you hold will lead you there...

This is also one of the times that English changed things up and gave bonus flavor. The other languages all say the same thing:

An ancient scroll in a hidden chest has led to a magic portal. On the other side, you find underground channels long abandoned, converted into a storehouse of untold riches. But not only treasure awaits here, for there are countless traps and other dangers...