Blizzard Entertainment released two Diablo III TV Commercials in addition to the one shown during The Family Guy TV cartoon. These variant TV Commercials show a few more cinematic frames not seen ever before showing a battle between Diablo-phist-aal (get it?) and Archangel Imperius, and another battle between Archangel Imperius and Archangel Tyrael in the High Heavens.
I just browsed through the Diablo III: Book of Cain. The first two images are not artwork from that book. It’s the first time we get to see this artwork. The dinosaur-like creature doesn’t resemble the artwork in the Trang’Oul page.
Check out our screenshots at the bottom (1080HD).
Looks more like Diablo and Impirius are working together.