The Lost Canals of Uznair
Continuation to Aquapolis and you can think of it as a level 70 version of Aquapolis with a Thavnairian theme.
Materia VIs and other rewards have a chance to drop in The Lost Canals of Uznair.
(During the stream, we showed some screenshots of the interior.)
We are planning the next update to arrive in Patch 4.1.