Pokemon: The Mirror Mirror Catastrophe! (Story Y)

Y, a Pokémon trainer from the Y universe, is training to become the league champion. Almost a decade after the murder of
his training partner, X, the guilt still weighs on his shoulders. One day, he is called by Prof. Acacia to aid in the experiment of using the recently created GTS to transport people as well as Pokémon from the newly discovered X universe. He is chosen as the representative of his own universe and is soon arranged to meet the representative of the X universe But what's this? The X representative is none other than X herself, ten years later! What will come of this discovery?

Later, it is discovered that the mighty Yveltal has approached the end of its life cycle and will absorb all forms of life, bringing and end to the universe! An ugly truth is faced; Force the dying Yveltal into the X universe to save their skins, or the Y universe will face universal extinction. A civil war between two universes ensues! Champion X faces Champion Y in the ultimate battle that will determine the lives of billions! Who will come out on top? Who will survive? What bonds will be broken? Stay tuned!

I am the writer of the original story of the same title. I'm redoing it here.
This is also a HUGE work in progress, it's gonna be a loooong story.