I know it happened in G1 briefly. But I would like to see a story where Megatron has fallen but to come back many years later but not to the Decepticons he left but to a new Decepticon Alliance under Starscreams Command. This time Starscream has truly learned the ways of a Leader and is not so easily scared off by Megatron. Screamer sees Megatron approach only to smile and laugh knowing that he is as strong as or even more so Powerful than Megs due to years of battling and adapting fallen bots powers to himself as Megs has done in the past. Not only that but all the Decepticons have followed Starsrcream through countless battles and wars and Follow Starscream to no end. Then a Great battle in sues between the two. I would like to see a more detailed and story driven idea like this animated or printed.