All the links, battles, badges, and basically, EVERYTHING, after you enter Luna Field around Luna City, where the Moon Gym is, is based on the R.E. League. The R.E. League was made and is run by KeroKato, of Reality's End
YOU MUST HAVE AN R.E. League ACCOUNT TO PARTICIPATE. If you still need an account, you may sign up for free in the R.E. League section of www.realitysend.f2s.com
Before you enter Luna City and the area that surrounds it, you can login to your pokebox, using the sign in area below, which will be available around most places in Luna City.