Early Dragonflight Alpha datamining hints at a possible underground zone coming in Patch 10.1.
The map database table has been updated in Dragonflight Alpha with an interesting new entry that references an underground zone.
The entry under ID = 2542 is named “Dragon Isles Underground [Warning: MUST be kept flagged “DEVELOPMENT MAP” until 10.1]”.
The 10.1 Dragon Isles Underground map ID is also referenced in the Map Difficulty database table as being limited to a maximum of 5 players. I think this may be a dungeon or some sort of scenario?
Even super early concept art of Dragon Isles depicts an old good-like structure that continues underground. Blizzard may have used this concept in Kul Tiras, however.
The Reddit WoW community speculates Patch 10.1 might add a Black Dragonflight zone that “is seemingly missing from the Dragon Isles map at first glance”. This is not entirely true as the Waking Shores are home to both Black and Red Dragonflights.
if you have any crazy theories about underground zones in Dragonflight, let us know in the comments!