So I just came up with this idea where if Sunset Shimmer counts as the 8th main pony then all the main pony's could be the robot master bosses and a could make a stage around each main pony which would be cool because there is a lot to work with there. So then Spike could be megaman which dose make sense because Spike is tiny and seems very weak, but then dose really cool stuff now and again. So then we would need a Dr. Wily. There's a lot of good options for this. I was thinking Nightmare Moon but almost any villain would work. Then we just need some some Wily stage bosses, Wily stages, and some allies for Spike and cool power ups for him to absorb from the pony masters.