Championing a Research Battle! (サトシ対チャンピオン・カルネ！VSメガサーナイト！！, Ash Against Champion - Diantha! VS Mega Gardevoir!!) is the 25th episode of Pokémon the Series: XYZ.
In Anistar City's Gym, Olympia warns Diantha of an incoming crisis in Kalos, sensing the "green flames" will pull people and Pokémon inside those flames. Diantha is also told Ash and his friends will play a major part in that crisis and asks what are the "deep green eyes" Olympia was referring to. Olympia shows an image of a Pokémon, which Diantha identifies as Zygarde. Elsewhere, Ash and Greninja are training. They start running to improve their speed, as both Ash and Greninja are dodging the trees standing in their way. As Greninja starts jumping from tree to tree, Ash tries to do the same, but slips off and falls down. Greninja lets Ash stand back up, who knows he must not fall behind, in order to control Greninja's mysterious power. They both run to Serena, Clemont and Bonnie, but Ash lags behind, allowing Greninja to come to the finish line before him. Ash falls down and nearly faints from exhaustion, so Serena offers him some water. Still, Ash feels he is getting closer to Greninja than before.
Suddenly, they hear something incoming. Diantha, who has been told she has to act in a commercial later on, uses a rope to lower down to the heroes, greeting them. Diantha admits she has come to see them, after hearing about Olympia's vision. From a bush, Meowth and James are watching this event, though Jessie comments how Diantha's beauty, talent and popularity are nothing compared to Jessie's. Diantha shows the heroes an image of an island, which was bustling with life, and is now corrupted by a giant tree. Diantha has heard many other islands are starting to look like this, fearing this is the start of the crisis of Kalos, which leads them to believe Zygarde is involved as well. Team Rocket notices the image, remembering they encountered Z-2 as the being, which was taken away by the men in glasses, Team Flare.
Diantha explains if there is a disturbance of order in Kalos, it is said Zygarde, from a deep cave, would reveal itself and protect Kalos itself. Clemont recalls Olympia spoke that they are to have some involvement in the crisis as well. Diantha asks them has there been anything strange they noticed around. The heroes wonder a bit and Bonnie tells about Ash's Greninja. Diantha is told about Olympia's prediction about Ash and Greninja. Wondering about this, Diantha requests a battle with Ash, sending her Gardevoir to battle Greninja. James and Meowth plan on stealing Gardevoir, while Jessie claims it is still nowhere near her beauty. Clemont prepares his Mini Clembot, to use the devices on Ash and Greninja to measure their pulses. Recalling his previous battle with Diantha, Ash asks of Greninja to win, no matter what.
The battle starts with Greninja using Cut, but Gardevoir dodges, without Diantha's commands. Greninja launches Water Shuriken, but misses once more. Greninja tries to use Cut, but Gardevoir constantly dodges it, even Greninja's Aerial Ace. Ash fears the battle will end like the last time with Pikachu, while Diantha does not see anything different from this Greninja. Gardevoir uses Shadow Ball, but Greninja uses Double Team, causing Gardevoir to miss. Gardevoir launches more Shadow Balls, managing to hit the real Greninja. Greninja retaliates with Water Shuriken, but Gardevoir evades the attacks. Gardevoir uses Moonblast, hitting Greninja and sending him onto a tree. Having an idea, Ash has Greninja use Water Shuriken on Gardevoir, who dodges. While Gardevoir is distracted, Greninja immediately uses Cut, hitting Gardevoir, surprising Diantha and Gardevoir. Clemont notices Ash and Greninja's pulses are synchronizing. In a moment, with Ash and Greninja's feelings as one, Greninja transforms itself; startling Diantha for such a power, seeing this is what makes this Greninja so unique.
Greninja speeds up to use Cut, but is countered by Gardevoir's Shadow Ball. Thinking the Greninja could be tied with Olympia's prediction, Diantha hopes to find the answer in the battle. Greninja uses Water Shuriken, which is stopped by Gardevoir's Shadow Ball. Gardevoir tries to, but fails to dodge Greninja's Cut. Greninja speeds up to use Aerial Ace, while Diantha touches her Key Stone, Mega Evolving her Gardevoir and stopping Greninja's attack. Despite this, Bonnie and Serena cheer on for Greninja, while Ash urges Greninja to continue the battle. Greninja uses Water Shuriken, which collides with Mega Gardevoir's Shadow Ball. Greninja uses Aerial Ace, but Mega Gardevoir stops the attack with Reflect. While Greninja uses Double Team, Clemont notices the waves of the pulses are getting stranger. Mega Gardevoir uses Reflect again to counter Greninja's Cut, while Ash urges Greninja to grow stronger.
In that moment, Greninja's water aura disappears, as it grows a pair of blue wings, which transforms into a Giant Blue Shuriken and descends down to use Water Shuriken. Mega Gardevoir uses Shadow Ball to counter the attack, but Water Shuriken slices through the Shadow Ball and hits Mega Gardevoir, injuring it badly. Ash urges Greninja to use Cut, but Clemont notices the pulses are not synchronized anymore, as Greninja and Ash snap out of their moment, and fall down from exhaustion. In addition, Team Rocket appears, using their device to capture Mega Gardevoir, claiming no power can destroy that rope. However, using its full power, Mega Gardevoir destroys the rope, and then blasts Team Rocket away with Shadow Ball. Mega Gardevoir shifts back into its original form; seeing Gardevoir quite exhausted, Diantha calls it back in its Poké Ball. Ash wakes up from his unconsciousness and is glad to see Greninja is also okay. Supported by Clemont, Ash stands up, and despite fainting from exhaustion, Ash feels he and Greninja did quite well today.
As the helicopter descends down, Diantha admits she does not know if Greninja's power is tied to the prediction, but is certain Ash and Greninja could master the power. Ash promises to get his final badge, as Diantha expects him to be at the Kalos League. Diantha bids farewell to the heroes and flies off in her helicopter. Inside, Diantha thinks there is some meaning to the power, if the heroes are involved in the incoming crisis, and something she should investigate further. Elsewhere, Xerosic shows Z-2 to Lysandre, who allows the final part of the project to start. While the heroes are packing to move on, Ash tells Greninja they have to become stronger to control the power, as well as to win in the Snowbelle City's Gym and participate in the Kalos League. With everything in place, the heroes set onwards.
- While Clemont, Bonnie, and Serena wait for Ash and Greninja to come out of the forest, Bonnie is standing to Clemont's and Serena's right. However, when Ash and Greninja come out of the forest, their positions are switched, with Clemont and Serena standing to the right of Bonnie.
- As Greninja gets ready to reach its final Ash-Greninja form, the star shape on its leg is cream instead of blue for a split-second.
- When the giant Water Shuriken forms, the webs on Greninja's right hand are missing.
- Greninja's Aerial Ace misses Gardevoir even though the move is unavoidable.
- When Ash and his friends are talking with Diantha in front of the helicopter, Greninja is missing the webs on both of its hands.
- In the final scene, when Ash is standing with Greninja and Pikachu is on Ash's shoulder, the brown stripes on Pikachu's back are shorter than normal in the first shot, yet they appear longer in the next shot.
- When Mega Evolving, Gardevoir's legs are colored green instead of white.
- When Mega Gardevoir uses Reflect for the first time to block Ash-Greninja's Aerial Ace, it is shown to be in its regular form.
|Pokémon the Series: XYZ|
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