If you haven't heard zygarde has new forms. The zygarde we all know, which lets face it, isn't that interesting is only 50% complete. They have announced for the new season of the animation new forms. Including individual cells, the core, a 10% form (which looks like a dog) and the complete form (which has a blue arm and a red arm). Both new forms look incredible compared to the old one. But with the announcement of new forms of zygarde means the possibility for a Pokemon Z game. There has been no confirmation of a Pokemon Z but it has been argued that since we have already met zygarde in x and y that there would most likely not be a Z. I myself have really hoped for another kalos game, lots of people have speculated they might do an x2 y2. But with the new zygarde forms it puts hope back out there for a Pokemon Z game. If you care to read the article on these new forms or see them for yourself head over to Pokemon.com.
- - - Updated - - -
I forgot to mention the new forms are for the new season in Japan. I am not sure how much further ahead they are in the series but it may be awhile before it is seen in other parts of the world. Ash's greninja also takes on a new form. It's bond with ash becomes so strong it takes on a form that resembles Ash's appearance. Apparently this has happened once before in the kalos region a long time ago. It is also talked about in the same article as the zygarde forms.