>>14365376The legendary Pokemon represent life, death, and order, and the pixie legend could be like Ratatosk, which if I remember correctly, can guide you through the realms.
Team Flare wants to make the world beautiful, but the have a twisted concept of it. They believe power is the purest expression of beauty, and so they want to use the war machine to subjugate the world, making them truly beautiful.
They plan to fuel the machine with Xerneas and Yveltal. In capturing or maybe even killing them, they disrupt the flow of life and death, which pisses the fuck out of the once docile Zygarde, who once kept to itself.
The World Serpent, or Jormungandr grows so quickly that it was trapped by being force to eat it's own tail. The Jormungandr, and the Ouroboros symbol which represents it, symbolizes the eternal balance of nature. One of the first events of Ragnarok is it letting go of it's tail (the natural balance being distrupted) and going berserk.
Once Xerneas and Yveltal become trapped, Zygarde becomes enraged and come to the surface. Since it's prime directive is to preserve order, it does everything it can, and I mean everything to establish order.