BioPaul is a rival of Ash in the Sinnoh region. He has a very closed personality and doesn't make friends very easily. He strives to find the strongest Pokémon he can possibly find and if they don't meet his expectations he releases them. He faced Ash in a full battle and managed to defeat him by using some of his older Pokémon where as Ash only used Pokémon that he had caught in the Sinnoh region save only Pikachu. The two of them made a pact to have a rematch at the Sinnoh League. The two faced off in the quarter-final round of the Sinnoh League. Ash took the early lead by defeating Paul's Aggron and Gastrodon. Paul fought back though defeating Buoysel, Staraptor and Torterra in a row. Infernape proved to be a powerful opponent and was able to defeat Paul. A bond between Ash and Paul was formed as they both began to respect each other after the battle. After loosing to Ash in the Sinnoh League, Paul returned home and then challenged Brandon of the Battle Frontier.
This is the first Pokémon the audience sees Paul with.
After Paul released his Chimchar it joined Ash's team. Click here to see info on Ash's Chimchar
Ash and his friends encountered an angry Ursaring while they were lost in a forest and it got mad and which started chasing them. While being chased by the Ursaring, Paul appeared and attacked the wild Ursaring with his Chimchar. Paul's Chimchar weakened it enough to capture it and Paul decided to keep it after scanning its strength with his Pokédex.
Paul caught this Pokémon to save Ash from it, but soon after catching it he released it as his Pokédex scan showed that it wasn't as strong as he would like
It's not made clear exactly when Paul caught his Azumarill, or even if he caught it in that form, but Ash and his friends first see it during Paul's battle with Roark, the Gym Leader of Oreburgh City. Azumarill is first Pokémon Paul sends out in this battle, to counter Roark's Geodude, but Geodude's Hidden Power managed to deflect Azumarill's Hydro Pump, and its following Rollout attack knocked Paul's Pokémon out in one hit before it could get off another attack. Later that day, Paul gave Azumarill to a kid at the Pokémon Center, saying it was a lost cause.
Paul's Weavile made its first appearance battling against Cynthia's Garchomp.
Paul's Murkrow first apperance was in battle against Cynthia and her Garchomp.
Paul's Torterra is his strongest Pokémon. Torterra made its first appearance in a battle against Cynthia's Garchomp.
Paul's Ninjask was first seen in a flashback fighting. Paul's Ninjask battled against Ash's Infernape during the quarter-final round of the Sinnoh League. Infernape was able endure Giga Drain and managed to hit it with a Mach Punch to K.O. it.
Elekid evolved into Electabuzz during a tag battle where it was fighting alongside Ash's Chimchar against Dawn's Buizel and Conway's Heracross.
Gliscor first appeared in a city it had become trapped in after being blown there by a violent windstorm.
Paul's Honchkrow was first seen in a flashback battling against Maylene's Meditite and Machoke.
Paul's Magmar was first seen in a flashback fighting against Maylene's Lucario.
Paul's Hariyama battled against Brandon's Regirock. It didn't last very long in battle as it was quickly overpowered by Regirock.
Paul's Lairon was first seen during a battle against Brandon's Regice. It was quickly frozen and defeated easily by Brandon's Regice.
Paul's Nidoking was sent out to battle against Brandon's Registeel but was quickly defeated.
Paul's Turtwig was seen in a flashback as Paul recalled the events that took place between his brother Reggie and Battle Pyramid King Brandon.
Paul's Magmortar battled against Pikachu during a full battle match at Lake Acuity. It evolved into a Magmortar in between encounters with Ash. It's strength and Flame Body proved to be very effective against Pikachu during the match at Lake Acuity which required Ash to withdraw Pikachu from the battle.
During his battle with Barry, Paul revealed that his Electabuzz evolved into a Electivire. It proved to be even stronger and was able to defeat Barry's Empoleon to win the match.
Paul's Gastrodon was the second Pokémon Paul sent out to battle against Ash during their full battle at the Sinnoh League. It proved to be a formidable opponent as Ash's Staraptor pinned it on the ground but a quick change by Ash to recall Staraptor which also proved to be a good strategy as Ash's Buizel defeat Paul's Gastrodon with an Ice Punch.
Paul's Aggron was the first Pokémon Paul sent out to battle against Ash during their full battle at the Sinnoh League. It was the first time that Ash and his friends had seen it in its evolved form. Ash's Pikachu battled against it for a bit until it was recalled and Infernape was sent out to battle. A swift Mach Punch managed to defeat Aggron.
Paul's Drapion was the third Pokémon Paul sent out to battle against Ash during their full battle at the Sinnoh League. It faced Buizel and managed to pin it with its tail.
Paul's Froslass battled against Ash's Pikachu during the quarter-final round of the Sinnoh League. Pikachu was able to hit it with an Iron Tail and after that point the match favored Pikachu. Pikachu defeated Paul's Froslass.