I don't know if any people have realized this, but this isn't the first time Megatron had half his face like he did in DOTM. He got half of his face ripped off in the G1 comics, by one of the Predacons if my memory serves me right. Anyone else catch on to that?
prime transformers on screen, and primes jet boots can bee seen during the dinobot charge when he shouts, "I'll KILL you!"
His head was disassembled to reverse engineer tech. Kind of like AOE. His face being ripped off is totally different though.