Despite the back story behind this new toy line pony, we can forget about Sunset Shimmer appearing in Season 4 for any kind of role whatsoever. Meghan McCarthy has confirmed this, thus suppressing the former rumors. It actually makes sense because for all we know, by the time Hasbro introduced this pony in the mask, Season 4 might have already been completed by the staff behind the TV show, or at least much of it. So now, Sunset Shimmer, despite having a name with practically the same meaning as Twilight Sparkle, is just a toy pony. See, bronies? Hasbro hasn't entirely taken control of the series. So get over Princess Twilight already!