I've come to realize a lot of people wanted a very dull movie. There's nothing wrong with including Marshadow if they tie it's shadow qualities to Ho-oh's rainbow qualities. I would have preferred Necrozma but this works too.
There was also blatant ignorance to the signs telling us this was something new though. Some of people, including myself, tried to talk about it but we were shot down pretty hardcore. This isn't even the case of false advertising or stupidly vague descriptions like we usually get with this series, they straight up told us this was a new story.Oh c'mon, blatant OS/Kanto teasing is blatant.