As the day comes to a close, Ash, Dawn, and Barry walk with Palmer along the festival. The vendors eagerly talk to him as Ash notices how famous Palmer is. He runs to the center of the road and brings out his Dragonite for a little demonstration. Brock shows up as Barry informs him who Palmer is. When Ash hears that Palmer was one of the top Trainers in Twinleaf, Ash challenges him to a battle, but Dawn and Barry are both eager to as well. Barry tells them about the upcoming tournament, where the winner will get the opportunity to battle Palmer. Barry also tells them that Palmer is a Frontier Brain for the Sinnoh Battle Frontier, leader of the Battle Tower, and known as the Tower Tycoon. After Palmer confirms the tournament for the next day, Ash looks forward to it, confident that he will win. At Dawn's house, Dawn cooks with her mother as they talk about how famous Palmer is and how they plan to battle. Brock intends to enter the tournament as well, but when he turns to Croagunk, he finds his Pokémon admiring a female Croagunk on television.
The next day marks the last day of the Twinleaf Festival as Johanna hosts the battle tournament. She brings out Glameow and Umbreon to kick off the tournament with some sparkle. As she gets the crowd excited, she is prepared to introduce Palmer, but he is nowhere in sight. Instead, he is at Team Rocket's booth, munching on their food. Ash and his friends seek out Palmer as they find him eating. Palmer doesn't seem to concerned at first, but when Johanna calls out over the loudspeakers, he panics and gives Ash a box of food before running to the field, followed by the rest. The tournament is back on track as Johanna introduces Palmer, who is ready to witness fierce battles and find the person worthy of challenging him, getting the crowd fired up. The battle rules are set as people will duel one-on-one, working up a ladder until a winner is found. The competitive spirit between Ash, Dawn, Brock and Barry gets going as Johanna mentions that the winner will get a gold trophy. The judge is Sayer, who oversees the tournament. Many battles quickly pan on screen as the timeline jumps to the final match, with Ash and Barry going at it. Ultimately, Pikachu bests Empoleon as Ash wins the battle tournament, upsetting both Dawn and Barry.
As the exhibition match gets underway, Johanna introduces Ash to the crowd, getting a good review. Palmer looks forward to battling Ash as he sends out Rhyperior. The Pokémon's sheer size surprises Ash as he checks with his Pokédex. Palmer informs Ash that no Trainer has bested his Rhyperior. After analyzing Rhyperior's types, he first believes that Speed will prevail, but based on previous Gym battles, he knows Palmer will be ready for that. Ash decides to summon Grotle to the field, as the type advantage is logical and to match up Rhyperior's strength with Grotle's strength and defense. Dawn thought Buizel would be better as Barry frowns on Ash underestimating his father. Sayer quickly reconfirms the battle rules as a one-on-one with no substitutions, and as the challenger, Ash goes first.
Grotle immediately fires Energy Ball, as Rhyperior stands firm and takes it with only minor damage thanks to Solid Rock. Though Palmer compliments Ash on Grotle's strength, he orders Rhyperior to use Rock Polish. Grotle fires Razor Leaf, but Rhyperior dodges quickly, shocking everyone at how fast it moved thanks to Rock Polish. Rhyperior gets close and launches Sandstorm. Grotle stands its ground as the attack surrounds and batters it. Rhyperior launches a Rock Wrecker, harming Grotle even more but isn't enough to take it out. While Jessie and James watch, upsetting Meowth who has to work, Ash has Grotle use Synthesis to heal since Rhyperior has to recharge from using Rock Wrecker. It taps into the healing move since the sandstorm has not blocked out the sun from above. Grotle recovers and uses Razor Leaf to neutralize the Sandstorm.
Rhyperior recovers and charges with Megahorn. Grotle prepares to use Energy Ball, waiting for Rhyperior to get closer. However, when Rhyperior closes in too quickly, he hits Energy Ball with Megahorn, and Grotle is forced to swallow it. The results shock everyone as Grotle taps into a large amount of power, a green aura radiating up into the air from the bushes on its back. Dawn takes note of it, thinking it would look good in a Pokémon Contest. The green aura dissipates, but Grotle's bushes continue to glow, with energy moving through them. Though as shocked as anyone else, Palmer has Rhyperior launch Rock Wrecker as Grotle rears up and slams its Rock Climb claws into the ground, creating a mountain on the field from underneath Rhyperior. Grotle continues and charges forward, ascending the rock formation and dodging the attack before ramming into Rhyperior and steadily driving it back with brute strength, impressing Barry and Palmer. However, Rhyperior uses its tail to stop Grotle's charge before landing a Rock Wrecker at point-blank range, creating a huge explosion and destroying the field mountain. As the smoke clears, Rhyperior is clearly exhausted, but Grotle lies at its feet, knocked out. Though somewhat disappointed with the loss, Ash takes it in stride as he compliments Grotle. Palmer presents the trophy to Ash for winning the tournament.
Later on, Barry talks to Ash about how he experienced battling Palmer, his strength apparent as Dawn sympathizes, reflecting on her battle with her mother. The thought of raising Pokémon brings Ash to reflect on how he lost to Paul and how he is able to raise strong Pokémon. The music starts as Barry quickly chows down to rush and sing the last song. Dawn remembers what she saw during the battle and plans to incorporate it into her next Contest Battle. Palmer walks over and suggests to Ash to go and challenge the Sunyshore Gym, hinting that Ash might shock the Gym Leader. Ash asks him to clarify why he would say that, but Palmer implies that when Ash gets to Sunyshore Gym, he will understand. The next day, Ash and his friends set off from Dawn's house, bidding Johanna farewell as they head to Dawn's next Contest. Barry races past the group as he plans to get to Sunyshore City first.