First, you see the different shields (not scannable):
When you scroll down, the list of the powers are categorized under each character:
And then when you click on a power (like Power of United Knights, #336), the shield and QR code (both scannable) appears. Note: If you use the QR code, you will need to select your time zone:
Just like that, you can fill up on the powers you missed (or haven't acquired yet)!
Here's the site: http://www.spyrius.org/nexo
AS ALWAYS, check with your parents before and during your visit to the blog.
(I added the link to the TABS above.)