I was quite surprised (I don’t know if it is a good or a bad surprise) to see Saruman saying “let me take care of Sauron” in Dol Guldur, with the blazing silhouette of Sauron behind…
I must admit though that the idea of having Sauron being the dark human like pupil in a red blazing aura… which , from afar, looks like a reptilian red eye…. is quite interesting indeed
(I hope I spoil nobody, but this “vision” was already present in the second movie, and as you all know I have always been fascinated with the representation of Sauron in the Tolkien universe)