>>28413686What? No
That meteorite was a key stone
"A huge meteoroid, far greater than any before, struck the planet, boring deep into the ocean and leaving behind it a crater larger than any other. The land born of this event later become known as Sootopolis"
"The great meteoroid was the first of many disasters to befall humanity. When it punched into the planet, the land cracked beneath it, and a great welling of natural energy poured from beneath Hoenn. Thirsting for that energy, Primal Kyogre and Primal Groudon once again woke.
"The people had a wish—a memory from a thousand years before... They wished that the Legendary Pokémon clad in emerald light would appear again. The huge Meteorite that lay at the heart of Sootopolis gave off a boundless brilliance. In its brilliance, it resembled a vast and powerful Key Stone. And once again, Rayquaza descended from whence it came in the heavens. The people fell to their knees before Rayquaza and made a wish for salvation. As they did, a great change came over the Legendary Pokémon. It was enveloped in blinding light. As the light receded, they beheld a Rayquaza beyond all knowledge— a sublime figure, incandescent with overwhelming life force."
Megastones was created in Kalos 3000 years ago using the ultimate weapon, in Hoenn was created during ORAS when the nature energy hoarded by Groudon/Kyogre was released (remember that new megastones appears after that). Meteorites have mega-shit because the ultimate weapon shoot to the space before the ray descend to land.
Xerneas/Yveltal -> life-death-evolution energy -> megastones
(Zygarde ->) nature energy -> life-death-evolution energy -> megastones
Also nature energy powered primal reversion (maybe Z power too)