To my understanding, Velothiid is the underground city built after the events of Landfall, as part of MK's C0DA, but mentiond in the Loveletter in Morrowind? And what exactly is Memory?

As a side question, does anyone think BGS might addapt elements of C0DA in a future game involving the Numidium, possibly trying to stop the events of Landfall from occurring? Perhaps in a game involving Elsweyr?

Underground city on the moon. Memory is the fractured remains of Nirn.