My awesome friend lent me Pokemon Black 2, so I transferred a bunch of Pokemon that I didn't have in my Pokedex yet, and also a Dialga, shiny Azelf and shiny Psyduck.
It was scary because I was really close to accidentally transferring his shiny level 100 Giratina because you can't even choose which box to transfer, you can only do the first one (or at least I couldn't choose.)