With Meloetta in their possession, Team Rocket's Giovanni controls Tornadus, Thundurus and Landorus in their more powerful Therian Formes though use of the reveal glass unlocked by Meloetta's presence and Meloetta's song. Ash, Cilan, Iris, Cynthia, and Ridley do their best to free Meloetta and save the world from Team Rocket. But forces stronger than Team Rocket are present, and Giovanni soon finds himself not able to control himself and sets Tornadus, Thundurus, and Landorus on a path to destroy Unova rather than take it over for Team Rocket.

Ash continues to train at Cynthia's villa until Ridley (a member of an ancient civilisation dedicated to protecting Meloetta) and his Golurk hear Meloetta's song and come to take Meloetta back. At first, Ridley assumes Ash is associated with the thieves, but this turns out not to be the case. Before Ridley can take Meloetta home, Team Rocket assaults the group and capture Meloetta and summon up the ancient Abyssal Temple through its power and song. The heroes try to fend off Team Rocket, but with Giovanni himself present they are too strong.

Ash's battle against Roxie for the Toxic Badge continues.

Ash challenges Brycen for the Icicle Badge, putting Scraggy, Krokorok, and Pignite up against Vanillish, Cryogonal, and Beartic.

Ash heads to Virbank City to face off against its Gym Leader, punk rocker Roxie from the band Koffing and the Toxics, in order to obtain his eighth Unova League Gym Badge.

After learning the Unova League conference will not be held for three more months, Ash, Iris, and Clian meet up with Cynthia, the Sinnoh Region Champion. She says she has come to Unova to participate in an exhibition match at the Pokémon World Tournament Junior Cup, held in Lacunosa Town, and Ash learns that the prize of the tournament is a battle with Alder, Unova's reigning Champion. As the four head out of Virbank City for Undella Town, they come across the legendary Melody Pokémon, Meloetta who seems to have fallen ill.

Upon arriving in Undella Town, Cynthia leads the gang to her villa where Dawn and Piplup are waiting for them. Dawn has come to Unova to perfect her Coordinator skills, and Cilan decides to have a Tasting Battle to see exactly what she can do.

With the semi-finals of the Pokémon World Tournament Junior Cup underway, and with the grand prize of having a battle with Alder on the line, Ash, Iris, and Trip go all out.

After meeting the Nimbasa City Gym Leader, Elesa, our heroes encounter an old friend with a surprise guest!

An encounter with Pikachu's rival from the past puts our heroes in the middle of a bullying confrontation!

After some convincing by a group of young challengers and Skyla’s grandfather, Skyla takes Ash up on his Gym Battle challenge.

At Ambiga Town, the local Don George holds a tournament called "Clubsplosion" to showcase Fighting-Type Pokémon, but all are welcome. Ash, Stephan, Bianca, Trip, and Georgia all enter the tournament, with Ash using his Scraggy. Ash and Scraggy's first opponent is Angus and his Simisage.

When the power goes out in Undella Town, the gang tries to help out when they discover a rampaging Dragonite may be to blame. When Iris discovers the Dragonite, she believes it is truly not bad but she is soon trapped in the room with the Dragonite along with Ash's Oshawott and Dawn's Piplup.

The Pokémon World Tournament Junior Cup begins, with rivals such as Trip, Georgia, and Burgundy showing up to take part in the tournament. After an exhibition match between Sinnoh Champion Cynthia's Garchomp and Unova Elite Four member Caitlin's Gothitelle ends in a no official winner, the first round begins. Iris is up first against Georgia, with Iris's newly captured Dragonite being pitted up against Georgia's Beartic.

What started as a trip to Milos Island to find Revival Herbs has turned into a cataclysmic battle of legendary proportions!

In search of scarce Revival Herbs, our heroes are now faced with the potential destruction of Milos Island!

While still staying at Cynthia's villa and training for the Unova League conference, Ash and the gang come across a fighting pair of Rufflet and Vullaby. It turns out they have both escaped the inexperienced Day Care Nurse, Layla. Whilst the manager is away, Ash, Iris and Cilan help Layla in the Nursery, but the ongoing conflict between the two Pokémon both craving Layla's attention continues.

With a bag full of revival herbs, our heroes have returned to Driftveil City and Ash is raring to battle Gym Leader Clay!

Ash, Cilan, and Iris make their way to Twist Mountain where they come across a fossil dig that has discovered a fossil Tirtouga. However, Team Rocket arrives and steals the fossil.

Stopping at Abtilbe Town's Battle Club, Ash meets his Tepig's former trainer Shamus who abandoned Tepig because he felt he was too weak. Angry, Ash challenges Shamus to a double battle with Snivy and Tepig going up against Shamus's Emboar and Heatmor.

The quarter-final matches of the Pokémon World Tournament Junior Cup take place, and Iris must go up against Dawn, pitting Dragonite against Mammoswine. In another match, Cilan and Crustle take on Trip and Serperior.

After Trip's match against Alder, the Junior Cup draws to a close and the contestants bid each other farewell. Ash, Iris, and Cilan meet Cameron, a young naive trainer who wants to travel with them. Dawn bids farewell as well, but not before having a practice match against Ash.

Ash, Iris, and Cilan help Cameron get to Humilau City where he wants to challenge Marlon for his own eighth Unova League Gym Badge. On the way, Ash and Cameron are separated from the group. Ash almost falls off a cliff, but then Cameron saves his life. Cameron has a "great idea" and he gets out what seems to be a "map", which was a table cloth. As they continue heading down a road, it starts to rain and then they take shelter in a nearby cave. Realizing that they didn't have any food, Ash, Cameron and their Pokémon are hungry as Meloetta leaves only to come back with an apple. Meloetta leads them to an apple tree where they harvest the apples to bring them back to the cave to munch on them. After they ate the apples (and Cameron's Riolu hiccups adorably), they decide to stay the night in the cave until the rain stops. Ash and Cameron exchange their goals in life. Ash wanting to a Pokémon Master while Cameron wanting to be the best Pokémon Champion in the world.

The Clubsplosion semifinals rage on. Bianca and Emboar battle Stephan and Sawk, while Ash and Scraggy battle Montgomery and his Throh. In the finals, Stephan and Sawk face Montgomery and Throh. Who will win the Clubsplosion Tournament?

Spending the day in Nimbasa City after Ash's fourth Unova Gym Badge win, Cilan has a special challenge in mind, while our heroes discover a fellow Trainer in need!