This (admittedly fuzzy) picture comes from an unknown trade show, where toy companies like Hasbro ignore movie spoilers in hopes of inspiring buyers to carry their merchandise. And what could be a more inspiring site than a sword-wielding Optimus Prime, leader of the Autobots, riding Grimlock in his dinosaur mode into some unknown battle?
I don't know what to say. I feel weird seeing a robot that can turn into a vehicle riding anything, to be honest. And Transformers 4 is still a Michael Bay movie, so it's entirely possible that Optimus will ride Grimlock to the song "The Boys Are Back in Town" or something equally banal. But on the other hand... Optimus is riding Grimlock and they are clearly going to kick many robot asses. I think I have some meditating to do.