During a promotional event in California, the jokers at GameStop duped a group of select "Super Smash Bros." players into believing a 10-year-old girl was some kind of fighting game prodigy.

As you can see in the video below, the girl, Karrissa, takes apart every challenger. Onlookers, along with the players themselves, are left dumbfounded. To top it all off, she even lays down some serious smack talk. "Are you not entertained!?" she exclaims after dispatching one opponent, stealing a famous line from Maximus in "Gladiator."

She earns herself the title of "Karissa the Destroyer," but she's not actually the one playing the game. As it turns out, professional gamer Liquid'KDJ was actually the proverbial "man behind the curtain" the entire time.

Watch the hilarious video below to see how it all went down.

"Super Smash Bros." for Wii U was released today (along with the first wave of amiibo figures, "Pokémon Omega Ruby" and "Pokémon Alpha Sapphire"), and there were midnight launch events all over the country last evening...but there was a huge event at Nintendo World in New York City. Check out a few pictures from that Nintendo World event below: