Mega Mewtwo Theory

So this theory is about Mewtwonite X & Y and Mewtwo's reason to have 2 mega evolutions, this theory is also about Charizardite X & Y and Charizard's reason to have 2 mega evolutions. It's odd how mewtwo and charizard are the only two pokemon to have two mega evolutions (so far). Doesn't it seem odd that if you were to have Pokemon Y (Yveltal) you would get mega mewtwo Y and that if you had Pokemon X (Xerneas) you would get mega mewtwo X. You can only get mewtwo after capturing these respective pokemon. Taking Yveltal to the cave with mewtwo in it triggers a reaction that results in mewtwonite Y upon catching mewtwo. (Taking Xerneas causes the reaction to end up with mewtwonite X)

If you were to take both of them (If a sequel came where you had to catch them both). The reaction would end up with the full Mewtwonite. The theory is that Mewtwonite X & Y are incomplete halves of the full mega stone. Charizard is a similar case. Energy is radiating from Geosenge town, depending on your version of the game, the half of the full charizardite would be X or Y. In the case that a sequel came where both can be caught at one time. (Assuming you could also get 2 masterballs to catch them) Their energies would merge the 2 halves together. In Y, the X stone is powerless and looks merely like another stone, and it works the other way round.

The only examples I could find were from the internet. I give credit to the original makers of the images.