'Doctor Strange' Initially Had a Different Villain in Mind
Two villains played pivotal roles in Doctor Strange. Kaecilius and, ultimately, Dormammu were the big bads, one bigger than the other, but president Kevin Feige had a different villain, other than Dormammu, in mind, in Nightmare.
“Kevin [Feige] made a very cogent case,” said director Scott Derrickson. “The trouble with starting with Nightmare is getting across the idea of the Dream Dimension as another dimension. The movie was challenging enough. It's already an exposition-heavy movie... Dormammu made the most sense. And he is the most present villain in the comics.”
Nightmare is the controller of the Nightmare Realm and Dream Dimension, and in the books has been a regular villain to Doctor Strange. Dormammu may have been selected for the intention of developing a new big bad beyond Thanos (as Dormammu is described as a "destroyer of worlds" in-film).
On Mordo, Derrickson said "I didn't want to do what the comics did and start off with Mordo just being and arch nemesis and a bad guy straight from the beginning," Derrickson told ComicBook.com. "I think with all so called villains, with all antagonists in any movie, you are only as invested in them as you are in their point of view and Mordo has a good strong point of view in this movie and the same is true of Mads Mikkelson's character.
"They're both men of idea, men of principles, men of beliefs and those are the kind of antagonists I enjoy watching, so we tried to make a movie with those kind of antagonists."
Source: Comicbook