When Keldeo brashly challenges Kyurem to a battle, it dominates the fight, easiy deflecting or dodging Keldeo's attacks, and the Boundary Pokémon ultimately breaks off Keldeo's horn with Shadow Claw. When Terrakion attacks Kyurem with Hyper Beam in an attempt to defend Keldeo, Kyurem deflects it then freezes the Swords of Justice with Ice Burn to prevent them from interferring with the battle. Keldeo then runs away during the middle of the fight out of fear, and Kyurem gives chase, determined to finish their battle.
Keldeo stumbles on the train that Ash and hisfriends are on, while Kyurem and his Cryogonal henchmen catch up and attack Keldeo, but they are repelled by Ash and his friends.
Kyurem pursues them and attacks them several times, only for them to be distractioned by Iris and Cilan. Eventually, Keldeo and Kyurem face off where they first met, and, despite Keldeo giving it its all, Kyurem retains the upper hand until Keldeo learns the move Secret Sword. When protecting its friends from a stray Freeze Shock attack, Keldeo takes major damage, making Kyurem the victor. Instead of finishing the battle, however, Kyurem respects Keldeo's courage and states that it was better to lose a battle than to lose one's friends.