It's PRIMUS! Seeing as how The Fallen's face was where the Decepticon logo comes from in the movie timeline, I noticed that none of the other Primes looked like they had Autobot logos for faces. It had to have come from SOMEwhere, so if it ever comes down to Primus being brought into the movie-verse, this be my take on him. If it seems a bit rushed, that's because it was. Took me less than a half hour. Edit: Contrast has been adjusted a bit.