Okay this has been bugging me for a while. Obviously, we know that during Wrath the utilization of undead dragons (frostwyrms) was a major part of the campaign in Northrend. Sindragosa was one of them.
I have one major question that’s been brewing in my mind:
Would these dragons retain their consciousness and be able to act like any other dragon in terms of taking on a humanoid form once freed from the Lich King? Would they retain their ability to intelligently communicate with others? Could they even /retain/ their ability to have a humanoid form once risen and undead?
Admittedly I don’t know much about dragon lore beyond the basics but this has been nagging the back of my head for a while.
Given that there aren’t any examples of such dragons shapeshifting, it’s really anyone’s guess if they can assume a visage or not. If we’re to assume it’s an inborn ability among them, I’d say there’s at least a chance they could if they’re of relatively sound mind. Granted, to an extent, that also assumes there are enough undead dragons like Sindragosa, who was at least of sound enough mind to speak. I imagine there could be other limitations, such as something to do with how visage forms actually work; which, again, there’s very little official lore explaining that.
I’m going to like the Shapeshifting section of Warcraft Wiki’s page on Dragons. Maybe it’ll help:
https://warcraft.wiki.gg/wiki/Dragon#Shapeshifting
We’ve had a few major dragons raised as various forms of undead, including Onyxia who was a gifted shapechanger.
None of whom did so as undead.