Endwalker's Hinted Mystery? What could it be that leads us into the new story?

[Iscah]

Corvos is almost certainly some kind of 6.X patch content. Aside of the story links, it's been established as a new location with a range of scenery that can be built with existing assets: it's close to Thavnair, so its tropical lowlands can borrow from there, while the temperate regions have been recreated in Labyrinthos so they just need to copy that but out in the open and with different architecture. And then of course we have the Allagan ruins that the G tribe is (or was) protecting, which provide more potential scenery, a story hook and possibly a source for relic weapons.

[EaraGrace]

Corvos is almost certainly some kind of 6.X patch content. Aside of the story links, it's been established as a new location with a range of scenery that can be built with existing assets: it's close to Thavnair, so its tropical lowlands can borrow from there, while the temperate regions have been recreated in Labyrinthos so they just need to copy that but out in the open and with different architecture. And then of course we have the Allagan ruins that the G tribe is (or was) protecting, which provide more potential scenery, a story hook and possibly a source for relic weapons.

My guess is other, like you said, relic or perhaps island sanctuary? Both?