The TV spots have featured the voice of Sheev plenty of times. In fact, a new line of his has debuted just about every other day.
At this rate, his entire dialogue in the movie will be revealed by the time the film is released. While his voice has been featured heavily, we haven’t gotten a single glimpse of the form he’ll be taking in the movie.
The best shot we have of what physical form Darth Sidious will be taking in the movie is from the trailer. He is partially off-screen and appears to be seated on some type of throne that may or may not be moving.
Don’t expect any upcoming TV spots to show the Emperor in his physical form. This is clearly a reveal that could be imperative to the overall plot and won’t be revealed until the film’s release this December 20.