Oh dear. It turns out that Karissa, the 10-year-old who proved to be destroying veteran Smash Bros fans at a GameStop event, was a publicity hoax that was paid for by the company. Investigative internet sleuths noticed that GameStop advertised on Casting Networks Los Angeles, advertising for actors to create the scene. The actors that participated were paid $350 for ten hours. Sad but true.
Thanks, Nathan S and Kaptain K Rool