>>50349376>Did gamefreak ever elaborate on where mega stones came from?Byproduct of the Ultimate Weapon getting fired.
>Why does Aerodactyl have a mega evolution?Presumably its effects were so devastatingly potent that dormant fossils were viable to form compatible Mega stones, and you could similarly say so for Mewtwo due to how powerful it is and how similar to the Ultimate Weapon it is on a "manmade tool of destruction" scale.