3) War for Cybertron (2010)

Now see, this is a good pre-Truck version of Optimus. Familiar but different enough so that he’s got a uniquely Cybertronian vehicle mode, the star of War for Cybertron and then Fall of Cybertron has enough classic elements but trades the harsh square lines of G1 for something smooth and rounded, and altogether bulkier. It makes sense, given the context of Cybertron and the war tearing it apart, that he doesn’t yet look like we’d come to know him when he lands on Earth.