The season begins with Ash Ketchum and his friends, Misty and Brock, arriving in the Johto region after their adventures in the Orange Islands. They are eager to compete in the Johto League and continue their Pokémon journey. Ash is determined to catch new Pokémon and improve his skills as a trainer. They quickly encounter a variety of new Pokémon, including the Johto starters: Chikorita, Cyndaquil, and Totodile.

As they travel, Ash and his friends participate in various Gym battles. Ash challenges the first Gym Leader, Falkner, who specializes in Flying-type Pokémon. The battle is intense, with Ash using his newly caught Pokémon, Pidgeotto, against Falkner's Pidgeot. After a tough fight, Ash emerges victorious, earning the Zephyr Badge. This victory boosts Ash's confidence as he continues his journey.

Next, Ash and his friends head to the Azalea Town Gym, where they face Bugsy, the Bug-type Gym Leader. Ash uses his Cyndaquil and Pikachu in the battle. Bugsy's Scyther proves to be a formidable opponent, but Ash's strategic thinking and teamwork with his Pokémon lead to another victory, granting him the Hive Badge. The group celebrates, but they are soon reminded of Team Rocket's constant attempts to steal Pokémon.

As they travel to the next Gym, Ash and his friends encounter Team Rocket, who are plotting to capture rare Pokémon. In a series of comedic and action-packed confrontations, Ash and his friends thwart Team Rocket's plans multiple times, showcasing their growth and teamwork. These encounters also highlight the bond between Ash and his Pokémon, particularly Pikachu.

The next Gym battle takes place in Goldenrod City against Whitney, the Normal-type Gym Leader. Whitney's Miltank proves to be a significant challenge, using its Rollout attack to devastating effect. After several attempts and a lot of frustration, Ash finally devises a strategy that allows him to defeat Miltank, earning the Plain Badge. This victory is bittersweet, as Whitney's emotional reaction to losing reveals her deep connection to her Pokémon.

Continuing their journey, Ash and his friends arrive in Ecruteak City, where they learn about the legendary Pokémon Ho-Oh and the history of the city. They challenge the Gym Leader, Morty, who specializes in Ghost-type Pokémon. The battle is filled with suspense as Morty's Gengar uses its ghostly abilities to confuse Ash. However, Ash's determination and the support of his Pokémon lead him to victory, earning the Fog Badge.

Afterward, Ash and his friends travel to the Whirl Islands, where they encounter the legendary Pokémon Lugia. They become involved in a plot involving Team Rocket, who are trying to capture Lugia. In a climactic battle, Ash and his friends work together to protect Lugia and thwart Team Rocket's plans. This experience deepens Ash's understanding of the bond between trainers and their Pokémon.

As the Johto League approaches, Ash and his friends prepare for the final Gym battle against Claire, the Dragon-type Gym Leader in Blackthorn City. The battle is fierce, with Ash using his strongest Pokémon, including Charizard and Pikachu. Claire's powerful Dragonite poses a significant challenge, but Ash's growth as a trainer shines through as he adapts his strategy and ultimately defeats Claire, earning the Rising Badge.

With all eight badges in hand, Ash heads to the Johto League. The tournament is filled with intense battles against various trainers, including familiar faces from previous seasons. Ash faces off against his rival, Gary Oak, in a highly anticipated match. The battle is intense, showcasing both trainers' growth and strategies. Ultimately, Ash loses to Gary, but the experience motivates him to continue improving.

The season culminates in the Johto League Championship, where Ash competes against the best trainers in the region. He faces several tough opponents, including a battle against Harrison, who uses a diverse team of Pokémon. The battles are filled with high stakes and emotional moments, as Ash pushes himself and his Pokémon to their limits. Despite his best efforts, Ash is ultimately defeated in the semifinals, but he leaves the tournament with a sense of accomplishment and determination to continue his journey.

As the season concludes, Ash, Misty, and Brock reflect on their adventures in Johto. They celebrate their victories and the bonds they have formed with their Pokémon. The season ends with Ash looking forward to new challenges and adventures, ready to continue his quest to become a Pokémon Master.

In the ending of Pokémon Season 4, "Johto League Champions," Ash Ketchum competes in the Johto League Championship. After a series of intense battles, he faces off against his rival, Gary Oak, in the finals. Despite a fierce competition, Ash ultimately loses to Gary. However, he gains valuable experience and learns important lessons about friendship and perseverance. The season concludes with Ash and his friends, Misty and Brock, reflecting on their journey and looking forward to new adventures.

As the final battle of the Johto League Championship unfolds, the atmosphere is electric with anticipation. The stadium is packed with fans, all eager to witness the showdown between Ash Ketchum and Gary Oak. The camera pans over the excited crowd, capturing the vibrant banners and the cheers echoing throughout the arena.

The battle begins with Ash sending out his trusty Pikachu, while Gary chooses his powerful Blastoise. The tension is palpable as the two trainers exchange strategies, showcasing their growth and the bond they share with their Pokémon. Ash calls for a Thunderbolt, and Pikachu unleashes a brilliant surge of electricity, striking Blastoise. However, Gary counters with a Water Gun, demonstrating his own skill and experience.

As the battle progresses, both trainers display their determination and tactical prowess. Ash recalls his previous encounters with Gary, reflecting on their rivalry and the lessons learned along the way. The scene shifts to Misty and Brock, who watch from the sidelines, cheering Ash on and expressing their unwavering support. Their friendship is a testament to the journey they have all shared.

The battle reaches its climax as Ash and Gary unleash their final Pokémon. Ash sends out his powerful Charizard, while Gary counters with his formidable Arcanine. The two Pokémon clash in a spectacular display of strength and strategy. Ash calls for a Flamethrower, and Charizard breathes a torrent of fire towards Arcanine. The crowd gasps as the two attacks collide, creating a massive explosion of energy.

In the aftermath, both Pokémon are exhausted, but Gary's Arcanine manages to stand tall, securing the victory for Gary. Ash, though disappointed, approaches Gary with respect, acknowledging his rival's skill. The two share a moment of camaraderie, realizing that their rivalry has pushed them both to become better trainers.

As the championship concludes, Ash reflects on his journey through Johto. He realizes that while he may not have won the title, the experiences and friendships he has forged are invaluable. Misty and Brock join him, and they celebrate their adventures together, vowing to continue their journey as friends.

The final scene shows Ash, Misty, and Brock walking away from the stadium, filled with hope and excitement for the future. They discuss their next destination, hinting at new adventures that await them. The camera zooms out, capturing the trio as they head towards the horizon, ready to face whatever challenges lie ahead. The season ends on a note of optimism, emphasizing the importance of friendship, growth, and the journey itself.

In the fourth season of Pokémon, titled "Johto League Champions," there is no post-credit scene following the episodes. The episodes typically conclude with a brief recap or a teaser for the next episode, but they do not feature any additional scenes after the credits. The focus remains on the adventures of Ash, Misty, and Brock as they continue their journey through the Johto region, culminating in their participation in the Johto League. Each episode wraps up the storylines presented without any extra content after the credits.

In season 4, Ash catches several Pokémon in the Johto region, including Heracross, Donphan, and Tauros.

In the Johto League, Ash faces several rivals, including Gary Oak, who is his long-time rival, and Harrison, who becomes a significant competitor during the league.

The Johto League Championship is significant for Ash as it represents his growth as a Pokémon Trainer and his quest to become a Pokémon Master, culminating in his participation in the league battles.

In his final battle in the Johto League, Ash uses his powerful Pokémon, Charizard, along with other team members like Pikachu and Kingler.

In the Johto League Champions season, Team Rocket continues their antics, attempting to steal Pokémon and disrupt Ash's journey, often providing comic relief and challenges for Ash and his friends.

In the Pokémon season 4 titled "Johto League Champions," the series maintains a family-friendly tone throughout. However, there are a few scenes and aspects that might be considered potentially objectionable or upsetting for children or sensitive viewers:

1. Battles and Conflicts: Pokémon battles can sometimes be intense, with Pokémon getting hurt or showing signs of exhaustion. While the battles are not graphic, the competitive nature may be a bit intense for some viewers.

2. Team Rocket's Antics: Team Rocket often engages in schemes that involve stealing Pokémon or causing trouble. Their antics can sometimes lead to mild peril for the main characters and their Pokémon, which may be unsettling for younger viewers.

3. Emotional Moments: There are scenes that involve characters feeling sad or disappointed, particularly when they face losses in battles or when Pokémon are separated from their trainers. These emotional moments may resonate deeply with sensitive viewers.

4. Rivalries: The competitive nature of the Pokémon League can lead to rivalries that may include taunting or teasing among trainers, which could be perceived as negative behavior.

5. Mild Scares: Some episodes feature Pokémon that may appear intimidating or have a darker theme, which could be a little frightening for very young children.

Overall, while there are moments that could be seen as upsetting, the series is designed to be suitable for a young audience, with positive messages about friendship, perseverance, and teamwork.