Pokémon >> Season 16

Bonnie and Clemont get into a fight after Bonnie wondered off to look for Chespin and when they encounter two brothers and their Meowstic having a rivalry, it gives Clemont a chance to teach Bonnie a lesson.

Korrina's grandfather Gurkinn tasks her with more training to rein in Mega Lucario, and Ash and company accompany her as they travel to Pomace Mountain only to fall into a trap laid by Team Rocket.

Korrina finally finds the Lucarionite, but after using it, she loses control of Mega Lucario, who is much too strong for Pikachu to defeat. Her grandfather Gurkinn must step in and take care of matters, with his own Mega Lucario.

Ash, Serena, Clemont, and Bonnie help Korrina and her Lucario find the Mega Stone Lucarionite in Geosenge Town's caves, only to come face to face with a Blaziken protecting the caves.

Ash and friends meet up with Korrina and her Lucario, and soon discover that she is the Shalour City Gym Leader, and she seems to possess a Mega Stone.

Upon arriving in the next town, Ash learns that the Kalos Region Champion Diantha will be holding an exhibition match, but he misses out on the sign up deadline. He heads to Professor Sycamore's lab, being tasked to help in his research on Mega Evolution, when he meets Diantha there by chance. She allows him a friendly match, Pikachu against her Gardevoir, and she shows she knows what Mega Evolution is.

While on the road, Serena makes some Poké Puffs for Pikachu and Fennekin, but her cooking skills are attacked by Miette, who has the Meringue Pokémon Slurpuff. The two decide to head to the next town and hold a Poké Puffs Contest to see who is the better pastry chef.

Ash and his friends make it to Cyllage City, where Ash plans on challenging the Gym Leader Grant. Having already seen his strategy with Onix at the Battle Chateau, Ash plans on having Froakie face the Rock Pokémon in battle, and later Pikachu against Tyrunt.

Ash, Serena, Clemont, and Bonnie meet up with Alexa again, who is covering the new fossil exhibit at the Ambrette Town Museum, meeting the revived fossil Pokémon Amaura and Aurorus in the museum's cold storage. However, Team Rocket arrives to steal Amaura, leaving Ash and his friends on a rescue mission.

While heading towards the next city, the group sees a man escaping from Officer Jenny and along the way find a Scatterbug that fell out of the man's truck. It turns out that the man is a Pokémon poacher who has been capturing Vivillon of different patterns and the group decide to help Jenny catch him.

While on their journey, the group stops for lunch when they are interrupted by two Pancham. However when Team Rocket attacks, the Pokémon get separated from their trainers. As Ash and his friends try to reach Pikachu, so does Team Rocket, but they cross paths with a Pangoro along the way.

Before heading to Cyllage City, the group decides to stop by the Sycamore Pokémon Lab. Team Rocket decides to kidnap Professor Sycamore, as well as Serena and Bonnie, to pry the professor's mind for the secrets behind Mega Evolution, while Ash and Clemont have to deal with a gluttonous little Chespin with a penchant for macarons.

Upon returning to Lumiose City, the group meets up with Clemont's and Bonnie's father Meyer who reveals to Ash and Serena that Clemont is Lumiose City's Gym Leader. Meyer also reveals that the Clembot, a robot Clemont had built to look after the gym in his absence, has gone haywire. Ash and Clemont infiltrate the gym to beat the Clembot in a Pokémon battle to take back the Lumiose Gym.

Ash is introduced to the world of Rhyhorn racing, and Serena, whose mother is a famous Rhyhorn racer, coaches Ash in the upcoming race. Meanwhile, Team Rocket has their sights on capturing Pikachu and the Racing Rhyhorn.

Ash arrives in the Kalos Region with Alexa, who reveals her sister is a Gym Leader, but she seems to be away.