>>18274782This is true, and world building stuff like this is cool too, but aside from that, Mewtwo doesn't do anything.
You COULD argue that it's better this way, and I'd agree with you for Kanto Mewtwo, as finding it alone deep in the cave was spoopy as shit, but in Kalos, it's just sitting in a hole in a wall for some 12 year old to shit down its neck and steal its Megastone.
Zygarde on the other hand captured the feel of finding a legendary deep in a cave perfectly. It wont happen, but I'd rather have a small Mewtwo-centric story next game, and leave Zygarde as the mysterious creature in the cave.