Dragon Age 4: 11 Things We Learned From The Behind The Scenes Gamescom Feature
7. (Possibly) Nevarra
The large, onion-roofed buildings in a city full of waterfalls implies an entirely new city in Thedas - possibly Nevarra, given its prominence in recent content.
It is unclear which part of Thedas this city really is, but with Nevarra and Nevarran characters, including necromancers, featuring heavily both in the Tevinter Nights short story collection as well as the concept art presented in the feature. It could be Tevinter, but the concept art veers more church-like, in contrast to Tevinter's sharper architecture.
A very interesting character keeps popping up in the concepts as well - a person with what appears to be a green, flaming skull face either as a mask or their actual face, though the rest of them appears flesh and bone corporeal.
It's not certain whether this is some kind of advanced necromancer, or a particularly powerful and willful spirit riding in a corpse - or both, showing them working with other servile corpses in what is likely Nevarra's Necropolis.
Whoever this priest-like Ghost Rider esque being is, they also appear in the "hero lineup", which implies they will be another of the many intriguing possible companions in this game.