Kyurem is one of the featured Pokémon in Kyurem VS. The Sword of Justice.

Having been born at the same time as Reshiram and Zekrom, Kyurem is considered the strongest Dragon-type Pokémon in the world. It can harness the powers of both Reshiram and Zekrom at will, allowing it to transform into White Kyurem and Black Kyurem respectively. According to Keldeo, one cannot become a Sword of Justice until one defeats Kyurem, who the Colt Pokémon is eager to fight against in order to become a member of that position.

(Source: Bulbapedia)