With Nintendo still playing dumb with regards to releasing any solid information regarding the widely speculated upon Pokemon Z, theories are flying and fans are grasping at whatever straws are available whilst we wait less-than-patiently for some official information.
It's been pretty widely accepted for a while now that the focus of Pokémon Z would be the lesser legendary Zygarde introduced in Pokemon X and Y alongside the core narrative-related legendaries, Xerneas and Yveltal. You could've played through the previous games without encountering Zygarde if you skipped the Terminus Cave, so it's not exaggeration to say that it had a much lesser part in these games.
Anyway, recently leaked images from Japan's CoroCoro magazine (see above) set this theory alight with speculation as the pages appeared to show new forms of Zygarde, the Pokémon that the upcoming game will allegedly be concerned with.
It's believed that Zygarde takes it's name from zygote - a cell formed through fertilisation. The zygote's genome contains all of the genetic information necessary to form a new individual, and is the starting point of the development of life. Zygarde's various forms certainly reflect this.
Cell: Single cells that make up Zygarde, they have no consciousness of their own and are found scattered throughout the world.
Core: A self-aware core, essentially this is Zygarde's brain.
10% Form: A dog-like form that the core takes when it gathers 10% of it's cellular structure from absorbing nearby cells.
- 50% Form: A serpent-like form that the core takes when it gathers 50% of it's cellular structure from absorbing nearby cells. This is the legendary encountered by the player in the Terminus Cave in Pokémon X and Y.
- Complete (100%) Form: A more humanoid form, this is the perfect form of Zygarde that the core takes when it gathers 100% of it's cells. Supposedly stronger than the X and Y legendaries, Xerneas and Yveltal, it is linked to the ecosystem as guardian/protector (see image above).
The Xerneas & Yveltal Theory
So if the Zygarde cells are supposedly scattered throughout the world, how come we haven't encountered them before?
YouTuber dookieshed posited the theory that the Zygarde encountered in Pokémon X and Y has in fact absorbed all of the individual cells available in the world. The reason it isn't in it's 100% form is because it still has two components to fuse with - Xerneas and Yveltal.
This does make a lot of sense given the way the final form appears - with red cells on it's left wing and blue on the right. It also feeds into the mythology of the three legendaries.
Xerneas and Yveltal represent the two sides of Ying and Yang. Xerneas is the giver of life with base moves like Aromatherapy and Heal Pulse. Yveltal on the other hand is a drainer of life, utilising Oblivion Wing to drain energy from the target Pokémon. Zygarde, according to reports, exists to balance out the ecosystem thus by absorbing the two legendaries who are always at war it would bring a resolution or balance to the world.
That's the theory anyway.
Since we met the 50% Zygarde in Pokémon X and Y, perhaps this means that we'll encounter an earlier version of the Pokémon in Pokémon Z when it finally rolls around, collecting the cells and levelling it up for some grand purpose over the course of the game. Of course this is all just speculation at the moment, so I guess we'll just have to wait until we get the official line from Nintendo.