Barry's Empoleon was Barry's starter Pokémon and his most powerful fighter.
Empoleon debuted in the same episode as its trainer, where it battled Ash's Pikachu. Although it proved to be a powerful opponent, Pikachu managed to win the battle. Empoleon would later battle Pikachu again in order for a chance for Barry to battle Palmer but Pikachu won again.
While Barry trained on Iron Island Empoleon, like all other steel types on the island except Riley's Lucario, went crazy due to the activities of Team Galactic. When the villains left the island it returned to its normal self.
After Ash caught Gible, Barry decides to battle it with Empoleon. Drill Pecks and Steel Wings hit Gible in a fashion it utilizes simultaneously. When Gible dodged Empoleon's Hydro Cannon with Dig, Empoleon used Hydro Cannon in the hole, creating an eruption of light. Empoleon sends an unmastered Draco Meteor with Steel Wing at Piplup. Empoleon used Hyper Beam against Dragon Pulse. When Gible is tired, Empoleon raps it up with Hyper Beam.
In Fighting Ire with Fire, Ash and Barry have a 2 point 3-3 Pokemon Battle. Ash starts with Monferno and Barry starts with "Guess Who?", Empoleon. Empoleon starts with Drill Peck, but is hit by back-to-back Mach Punch and Dig. After the 2nd Mach Punch, Empoleon finishes it off with Hydro Cannon. Before, it was seen knocking out a Trainer's Mothim with its newly-learned Metal Claw.
Empoleon was used during Barry's battle against Paul, where it blasted his Magmortar with Hydro Cannon so Paul recalled his Fire type Pokémon. Empoleon was recalled when Paul sent out Ursaring. After Barry's Hitmonlee was defeated, Empoleon briefly fought Ursaring who was then replaced by Electivire. Empoleon fought bravely, activating Torrent during the battle in a final desperate attempt to defeat the Electric type, but Electivire blocked its Hydro Cannon with Protect and finished it with Thunder.