Thultanthar

Thultanthar, translated as 'Shade' in the Loross language was a Netherese flying city. Thultanthars high mage known only as Lord Shadow had been experimenting with the Plane of Shadow for some time and had successfully shifted the entire city into the Plane of Shadow mere days before Karsus cast Karsus' Avatar and temporarily destroyed the Weave in the Year of Sundered Webs (-339 DR). For some reason though, Lord Shadow could not move the city back to the Prime Material Plane. It took weeks but eventually, they managed to return to Netheril, or at least what was left of it. Searching for survivors for days, the city floated over the ruins of the Netherese empire. Finding none, Lord Shadow assumed it was the work of the Phaerimms and began planning his revenge. He stopped though, when he realised that one city was not match for them and that his subjects were likely the last of the empires people. He abandoned those plans and retreated back into the Plane of Shadow, vowing that one day, they would return and reestablish the empire. The city's clerics of Shar cast divinations and saw what had really happened, but only informed the noble families, presumably on the whim of Shar herself for some reason. The excursion into the Plane of Shadow, due to unforseen circumstances has lasted much longer than Lord Shadow anticipated. So for over 1700 years, the inhabitants have battled the Malaugrym and the other shadowy horrors of the realm, while each generation became gradually more attuned to the plane itself. In the Year of Wild magic (1372 DR), Thultanthar returned to Faerun, floating over the Dire Wood. Almost immediately, the princes of Thultanthar (now known more commonly by its translated name of Shade) have been busy looking for Netherese ruins and artifacts as well as spying on people and places that could possibly hinder their ultimate goal of creating a new Netheril in their image.