Crossing the Battle Line! (Japanese: ヒカリはじめてのジムバトル！！Hikari's First Gym Battle!!) is the 67th episode of Diamond & Pearl series, and the 533rd episode of the Pokémon anime. It first aired in Japan on February 14, 2008 and in the United States on July 26, 2008.
Dawn has challenged Maylene, the Veilstone Gym Leader, to a battle that's scheduled for the next day. This gives both Dawn and Ash time to train—Ash and Reggie, Paul's older brother, are helping Staravia learn the Brave Bird move. Ash makes himself a moving target to help Staravia improve its concentration, a selfless move that surprises Paul's Electabuzz. That night, after all the training is done, Dawn discusses her Gym challenge jitters with Ash and Brock.
The following morning, the challenge begins: a three-on-three battle! Maylene starts with her Meditite and Dawn is so nervous she almost freezes, but Ash's cheering gets her back into the game. Dawn chooses Buneary; she's unused to this style of battling, but she can also use Contest-style moves to cover for her weaknesses. However, Maylene and her Pokémon move in perfect sync, and Buneary is no match for their power.
Dawn sends out Ambipom next, hoping to draw on the battle experience it gained with Ash. Ambipom defeats Meditite but falls to Maylene's next Pokémon, Lucario, which packs a powerful Bone Rush attack. Now Dawn has to rely on her trusty Piplup, surrounding Lucario with Whirlpool to try and get the upper hand. Lucario still comes out the victor, but the battle leaves both Dawn and Maylene excited about the battles to come. Now that Maylene is ready to resume her Gym Leader duties, it's time for Ash to finish teaching Brave Bird to Staravia so he can challenge Maylene himself...
After the events of the previous episode, Dawn announces her plan to have a Gymbattle with Maylene, but Maylene asks to postpone it until the next day for preparation. While Pipluptrains with Buizel, Reggie calls to Ash to train as well. Brock asks about Dawn's strategy for the battle. Dawn decides to use Piplup since it knows Peck, Ambipom for her prior battle experience and Buneary's Bounce. Reggie's Staraptor demonstrates Brave Bird, smashing a rock top to pieces. Staraptor takes some damage, something Reggie points out. While Electabuzz munches on a Berry, Staravia makes its first Brave Bird attempt, but it comes apart mid-flight and Staravia crashes to the ground. Ash tends to Staravia as Reggie notes that a moving target would be much better for Staravia's concentration. Ash volunteers to be the target despite the danger. Staravia makes another attempt as Ash runs, eventually dodging the attack and giving Staravia its first successful attempt.
Ash continues to train with Staravia, inspiring Dawn to train more as well as shocking Electabuzz. Reggie mentions to Brock that Ash is the opposite of Paul in terms of training, being more involved. He also asks about Dawn's intention to battle Maylene as her Coordinator career makes it difficult for Reggie to believe. Brock notes that it is to help Maylene's confidence as well as her own. In the Gym, Maylene tries to Meditate, but her stomach rumbles, angering Lucario, but she mentions that she is training seriously and asks Connally to be the referee. Team Rocket wants to steal Lucario, but Jessie notes Lucario's power, preferring to take one of Maylene's other Pokémon instead. During the night, Ash and Dawn check on their training progress, which is going well for both. Dawn is nervous about the Gym battle, which Ash sympathizes, something he felt many times before. Brock mentions his experience at Pewter and how he learned from his challengers, which could allow Maylene to learn as well.
Dawn challenging the Veilstone Gym
The next day, Team Rocket stakes out the Gym with cameras as they notice Ash and his friends arriving. When Dawn announces her challenge intention loudly, Team Rocket is also stunned at her challenging the Gym. Dawn and Maylene take positions as Reggie, Ash and Brock watch. The battle is set for three-on three with only Dawn being allowed to switch Pokémon during the battle. Maylene sends out Meditite first as Dawn checks her Pokédex. They notice Dawn's tension causing her to hesitate, but Ash shouts inspirational words, getting both of them relaxed.
Dawn summons Buneary first. Buneary jumps rapidly as the duel begins. Buneary goes first with Bounce, jumping and coming down, but Meditite uses Detect, dodging the attack. Meditite uses Drain Punch, everyone noticing Maylene mimicking her Pokémon's movements and demonstrating synchronization. Despite a spin-dodge, Buneary takes a severe hit. Buneary struggles to get up as they notice Dawn's lack of battling experience. Buneary fires Ice Beam, freezing Meditite solid. Buneary charges, but Meditite uses Confusion to break from the ice and send ice shards at Buneary, which the Pokémon dodges. Another Confusion sends Buneary into the air and tosses the Pokémon down to the ground, but Buneary uses its flexible ears to soften the impact and go right into a Bounce attack. Meditite counters with Drain Punch, both attacks connecting and causing an explosion. Both Pokémon are shaken, but Buneary took too much damage, its legs buckling before falling down, knocked out.
Lucario notices Maylene's improved attitude as Dawn summons Ambipom. Ambipom fires Swift, coming around in a circle and hitting Meditite from all angles, similar to a Contest-style move. Meditite uses Drain Punch as Ambipom blocks with one of her tails before using Double Hit to knock out Meditite. Maylene smiles as she notices Dawn's approach is similar to a Contest Battle. She summons Lucario to the field, the Pokémon ready to battle. Everyone notices Lucario's improved attitude towards Maylene as her confidence grows. She tells Lucario to not let Dawn's Contest-style tactics confuse it. Ambipom uses Double Hit as Lucario uses Bone Rush to block both strikes and toss Ambipom against the edge of the battlefield, knocking her out.
They notice Lucario's stylish movements as Dawn summons Piplup as her final. Piplup fires Bubble Beam as Lucario dodges and fires Aura Sphere. The attack hits Piplup directly and tosses the Pokémon around, but it recovers. Piplup uses Whirlpool to trap Lucario in it before coming down the side with Peck. Everyone notes Dawn's Contest approach covering up the poor type matchup. Lucario uses Metal Claw to break the Whirlpool. Reggie notes Dawn's Contest approach awakening Maylene's battle spirit. Piplup fires Bubble Beam as Lucario charges forward and grabs Piplup with one palm before using Force Palm to toss Piplup back, paralyzed.
Watching from a camera, Team Rocket decides to go back to the original plan and try to steal Lucario. Piplup breaks the paralysis effect as Maylene and Lucario are both energized. Lucario fires Aura Sphere again as Piplup breaks it with Peck and lands a hit, tossing Lucario back but not critically wounding the Pokémon. Lucario fires Aura Sphere again as Piplup blocks with Bubble Beam, negating the attack and creating a smoke screen. Piplup charges into the smoke with Peck, but Lucario is not where Piplup expected. Lucario comes down from above with Force Palm, creating a massive explosion. When the dust clears, Lucario removes its palm from Piplup's head, leaving the Pokémon knocked out and giving the match to Maylene. Everyone commends Dawn's first battle and how Maylene has a much stronger spirit now. Ash compliments Dawn and is excited for his match against Maylene. Maylene thanks Dawn for helping her recover as Maylene prepares for her battle against Ash.