Ash Ketchum/Original series (Johto)

Season 3: The Johto Journeys
Ash heard that there was a region called Johto and traveled there to find and catch new Pokémon unseen in Kanto. He battled the Gym Leaders there and caught the three Starter Pokémon, just as he'd done in Kanto. Brock returned and left Professor Ivy (for unknown reasons) and Tracey remained at Professor Oak's Lab. During this season, Ash won two badges for the Johto League, by facing Falkner of the Violet Gym and Bugsy of the Azalea Town Gym. He also catches a Shiny Noctowl, had another battle with Misty and said goodbye to his Charizard as he left it at the Charicific Valley so it could become stronger.

Season 4: Johto League Champions
Ash won three more badges, but was delayed from having his sixth Gym Battle as the Gym Leader, Olivine Town's Jasmine, was preoccupied with caring for an ill Electric Pokemon, Ampharos, that fueled the lighthouse's power. Determined to get his Gym Battle, Ash traveled over to Cianwood City to get the medicine needed for Ampharos. Along the way he meets the Gym Leaders Whitney, Morty, Jasmine and Chuck, along with some new friends like Sakura, an aspiring Trainer and one of the 5 Kimono Sisters and reunites with Casey, whose Chikorita evolved into Bayleef. After his Gym Battle with Chuck, Ash and his mates traveled to the Whirl Islands on Chuck's suggestion to take part in the Whirl Cup Competition, a tournament for Water-type Pokémon.

Season 5: Master Quest
During this season, Ash finally collected the remaining three badges to enter the Johto League by beating Jasmine, Pryce and Clair. He also met Lance and stopped Team Rocket's latest scheme at the Lake of Rage and brought a Larvitar back to its mother. In the Johto League, he battled his old rival Gary and finally defeated him, bringing their long rivalry to an end, then fought Harrison from the Hoenn region, who had a Blaziken, a Fire-type Pokémon Ash had never seen before. To face it, Ash chose his trusty Charizard: the two Fire-types fought fiercely, but ultimately Charizard fainted and Ash lost. (However, Charizard managed to wound Blaziken badly enough to prevent Harrison from using it in his next match, which led to his defeat.) Ash then decided to travel to the Hoenn region, but sadly, both of his friends had to return home and thus would not be traveling with him this time.