I was thinking, what if the wound caused by Sentinel permanently damaged Optimus? As in, he permanently lost his left arm? the damage was too deep to be fixed without putting his life in jeopardy or something. I think it would be remarkably interesting to see him with his arm missing on the next movie, it would add a bit of a chronology to the trilogy [seeing a permanent change caused by the previous movie] and shake the image of Optimus being invencible while ALSO making him ten times more badass [even handicapped, he can kick ass and take names]. Also opens room for some drama if wanted ["I am no longer the Prime I used to be..."], with him growing tired of the war after all the shit that he had to put up with [his arm being the final reminder]. BESIDES, it would be sick to see Optimus fighting with one arm only. What do you guys think?