M15 - Bulbapedia, the community-driven Pokémon encyclopedia
Satoshi, Iris, and Dent are on a train to their next adventure in Roshan. As the train weaves through the mountain roads, our heroes spot an injured pokemon they had never seen before. It turns out to be the legendary Keldeo, a pokemon who's said to be the successor to the trio of "sacred swordsmen" who protect the earth and its pokemon. These swordsmen are none other than the legendary trio of Cobalon, Terrakion, and Virizion!
Suddenly, the strongest Dragon-Type pokemon Kyurem appears and attacks Satoshi and his friends! Kyurem has the power to transform into "Black Kyurem" and "White Kyurem," leaving Satoshi and his friends with no choice but to make a run for it!
This thrilling chase takes place takes place on both land and the air! Can Keldeo, Satoshi, and Pikachu overcome this danger and escape!? And how will Satoshi's and his friends' friendship awaken Keldeo's hidden power?