What Is It?
Super saiyan god super saiyan 2 or super saiyan blue 2 is a form above super saiyan super saiyan god super saiyan or super saiyan blue. Like how you get super saiyan blue is simler to how you get this form. How you achive this form is that you must combine super saiyan god power with super saiyan 2 ki and you would get this.
Power & Abilitys
Now in terms of power a super saiyan god or super saiyan blue multiplier has not yet been confirmed yet and probaly never will be uless Toyriama desides to. But other people around the internet are saying that the super saiyan blue multiplier is x200,000 or x10 more powerful then super saiyan god whuch apparently is x20,000. So if we want the super saiyan blue 2 multiplier then we will need to do 200,000 x2 because super saiyan 2 is x2 more powerful then super saiyan. So if we would do this math then we would get total x400,000. Now finally abilitys is it is simply all you power but is x2 more powerful.