Confirmed. Yup the "new" Pokemon is actually Mewtwo.

[Talal]

sales2099 said:
"New Form". Can people stop saying that?

This is a evolution of Mewtwo. It is so plain and obvious.

It's not an evolution Mewtwo is a legendary pokemon with 680 base stats. If it were an evolution just how much stronger will it get. It's a new form, quite a few legendaries have forms.