When you purchase your copy of either Pokémon Black or Pokémon White, you will have the chance to get Victini, the first Fire- and Psychic-type Pokémon. But this is a limited-time event. This cute fella also is a legendary and has a very helpful ability. Victory Star raises the accuracy of not just Victini but all of the Pokémon in your party.
To get Victini, you must purchase either title by April 10th and use your Nintendo Wi-Fi Connection to obtain the Liberty Pass. This item allows you to go to the location where Victini awaits you. The Liberty Pass will not be available after April 10th, so if you plan on grabbing, do so soon!