Familiarity Breeds Strategy! (Japanese: ライバル決戦！サトシ対シンジ！！ Rival Decisive Battle! Ash Versus Paul!!) is the 29th episode of Pokémon: DP Sinnoh League Victors.
Paul and Ash face each other in the League. Ash sends Pikachu and Paul his Aggron. Before that, however, Ash's Gliscor battled Dawn's Mamoswine, revealing Gliscor perfected Giga Impact. Barry was quite excited how Gliscor used the move, though Brock reminded him that Gliscor cannot move for a while after the attack is executed. Barry asked which Pokémon Ash was going to choose and this reminded Ash of his battle with Paul at Lake Acuity. Ash had given some thought and knew Paul was going to use experience he had from his previous battles against his opponents. Barry asked if Ash wasn't doing this the same thing, and Ash confirmed, but he looked what Paul learned, not Ash. Barry asked if he figured that out and Ash replied that he would see, which made Barry angry. Dawn had Piplup dressed for cheerleading, but in a different outfit. Paul contacted Reggie, who wished him luck. Also, Reggie was happy for Paul for meeting Ash, as Ash had a lot of influence on him. Also, Reggie advised Paul not to underestimate Ash and wanted Paul to win the League.
Dawn had overheard the conversation and asked Paul if that was Reggie. Paul ignored her and asked how was Ash doing. Dawn replied that he was training with his Pokémon and asked Paul if he wanted to get him. Paul refused and when asked why did he ask how was Ash, so he answered that he did not know and walked away. Paul admitted that he does not like Ash, as he is like Reggie, who talks about friends, trust and belief in the Pokémon. Dawn said that Ash is not Reggie. Paul replied that Ash is just another trainer he has to beat to advance in the League. Soon, they encountered Brock, Ash and Barry. Ash told Paul to make the next fight a great one, which Paul agreed to. Dawn reminded everyone about Cynthia's quote "When one life meets another life, something will be born". Barry was surprised to hear Dawn was a poet, but Brock corrected him, as it was Cynthia's quote when she had met Ash and Paul. Dawn thought that Ash and Paul will make something new, but did not know what that actually was, but knew that will be seen at the League. Paul turned back and told Ash they will see each other on the field.
Back at the field, Ash sent Pikachu and Paul his Aggron. Aggron uses Metal Claw, but Pikachu repels the attack with Iron Tail. Aggron uses Metal Sound, which affects not only Pikachu, but Meowth and Piplup, who have their Special Defense lowered. Pikachu retaliates using Thunderbolt, then follows with Volt Tackle. Aggron uses Flash Cannon and counters the move, preventing Pikachu's Volt Tackle. Ash calls Pikachu back, while Barry is under the impression of how Paul raises his Pokémon so powerful. Ash sends Infernape, which Cynthia recognizes as Chimchar, who evolved. Aggron uses Double Edge, so Infernape uses Flare Blitz to counter. While Infernape is damaged by recoil, Aggron is unaffected because of Rock Head, which allows Aggron not to be hit by moves that cause recoil damage. However, Aggron becomes burned and takes damage from the contact of Flare Blitz. Infernape uses Mach Punch and Aggron goes to stop it using Flash Cannon, but Infernape hits it before and defeats it.
Paul calls Aggron back. Team Rocket, Dawn and Barry are happy to see Ash winning, but Brock worries, as it is just one win, while more is to come. Paul sends Gastrodon, while Ash calls Infernape back and sends Staraptor. Paul sees a pattern of Ash's Pokémon, while Reggie sees Ash is using the Pokémon at their battle of Lake Acuity. Gastrodon starts with Muddy Water, but gets hit by Quick Attack. Gastrodon uses Muddy Water as a repellent against Staraptor in a way that Barry recognizes as Counter Shield, a move that was used against Fantina's Pokémon and in the battle between Ash and Paul. Ash has an idea and orders Staraptor to use Aerial Ace on Gatrodon's belly. However, Gastrodon evaded and uses Body Slam on Staraptor, binding him to the ground. Staraptor cannot move, while Gastrodon uses Water Pulse in the sky, which goes down. Brock sees Paul wants the move to hit Staraptor just before Gastrodon moves away.
Staraptor uses Close Combat on the ground and goes away, causing the Water Pulse to hit the ground. Gastrodon uses Ice Beam, causing Staraptor to fall down and Ash to call him back. Ash sends Buizel, so Paul sees Ash is even more pathetic and predictable. Paul sees Ash's Pokémon want a re-match dating back from Lake Acuity and Ash confirms. Gastrodon uses Ice Beam, so Buizel uses Aqua Jet and fuses with Ice Beam, making Ice Aqua Jet (which makes Barry very excited) and hits Gastrodon. Gastrodon uses Body Slam, but gets defeated by an Ice Punch. Ash now knows the true battle against Paul will commence soon. Paul calls Gastrodon and sends Drapion. Drapion uses Pin Missile, but the pins move in a strange way. Buizel uses Water Gun as a Counter Shield, which deflects the missiles. Drapion uses Cross Poison, but Buizel dodges and retaliates with SonicBoom. However, Drapion uses its tail to counter the move and binds Buizel. Drapion turns back and goes to attack Buizel continually.
Gastrodon (East Sea)
- Aggron was hit by Thunderbolt, even if it is a Rock-type Pokémon.
- As Buizel was about to be frozen while in its Aqua Jet, its mouth was orange.