I wanted to train up a few Scatterbug that I had traded for, so I put my regular team in the Battle Box, thinking that if I were challenged to a battle, I'd get to pick to use them instead.
So of course, I was challenged to a battle. I accepted, and when I got to the screen where I could pick which Pokemon are entered, I only saw what was currently in my party, and no option to get my Pokemon from the Battle Box.
Is this what the Battle Box is used for? Why couldn't I battle with the Pokemon in it?