Over more than 25 years of adventures in the Pokémon anime, Ash Ketchum has traveled through multiple regions, captured dozens of Pokémon, and ultimately fulfilled his lifelong dream of becoming the World Champion after winning the Masters Eight Tournament.

Along the way, every region introduced a standout Pokémon that helped Ash overcome Gym Leaders, rivals, Elite Four-level opponents, and even Legendary Pokémon.

Here’s a look at Ash’s strongest Pokémon from each region and why Pikachu still stands above them all.

Kanto – Pikachu

Although Charizard eventually became one of Ash’s greatest powerhouses, Pikachu has always been his most important partner since the very beginning.

Over the years, Pikachu has accumulated one of the most impressive battle records in the anime, defeating opponents far stronger than expected, including: Brock’s Onix, Regice, Latios, Tapu Koko and Leon’s Gigantamax Charizard. Its greatest achievement came during the Masters Eight Tournament, where Pikachu defeated Leon’s Charizard in the decisive battle that crowned Ash as the strongest Trainer in the world.

Why it’s No. 1: No other Pokémon has contributed more to Ash’s career.

Johto – Heracross

Ash rotated several reliable Pokémon throughout Johto, including Bayleef and Cyndaquil, but Heracross consistently stood out.

Known for its incredible durability and raw physical strength, Heracross played a key role during the Silver Conference, helping Ash finally defeat longtime rival Gary Oak. Though it appeared less frequently than Pikachu, Heracross always delivered when called upon.

Signature strength: Exceptional endurance and devastating Megahorn attacks.

Hoenn – Sceptile

If one Pokémon defines Ash’s Hoenn journey, it’s Sceptile. Beginning as Treecko before evolving into Grovyle and finally Sceptile, it consistently delivered victories throughout the Hoenn League.

Its most legendary accomplishment came later during the Sinnoh League, when it became the only Pokémon to defeat Tobias’s Darkrai, a feat that remains one of the anime’s greatest upsets.

Defeating a Legendary Pokémon cemented Sceptile’s reputation as one of Ash’s strongest partners ever.

Sinnoh – Infernape

Few Pokémon have enjoyed a character arc as memorable as Infernape. Originally abandoned by Paul as Chimchar, it flourished under Ash’s care, eventually evolving into one of his fiercest battlers.

With an estimated win rate of around 77%, Infernape became the cornerstone of Ash’s Sinnoh team.

Its defining moment came during the Lily of the Valley Conference, where it defeated Paul’s Electivire and completed one of Pokémon‘s most emotional rivalries.

Unova – Krookodile

Although Ash’s Unova journey remains one of the franchise’s more divisive storylines, Krookodile emerged as its brightest highlight. Even before evolving from Krokorok, it demonstrated consistency in major battles. Among its best achievements:

  • Defeating Iris’s Dragonite
  • Strong performances during the Pokémon World Tournament Junior Cup
  • Helping Ash in several key tournament matches

Its confidence and reliability made it Unova’s standout performer.

Kalos – Greninja

After Pikachu, Greninja is arguably Ash’s most beloved Pokémon. Its unique Ash-Greninja transformation reflected the extraordinary bond between Trainer and Pokémon, granting tremendous power that no ordinary Greninja possessed. Among its greatest accomplishments:

  • Defeating Sawyer’s Mega Sceptile despite the type disadvantage
  • Pushing Champion Diantha’s Mega Gardevoir to its limits
  • Leading Ash deep into the Kalos League

Although Greninja eventually remained in Kalos to protect the local ecosystem, it is still considered one of Ash’s strongest Pokémon ever.

Alola – Lycanroc

Lycanroc played a crucial role in helping Ash achieve his first-ever Pokémon League championship. Throughout the Alola series, Lycanroc repeatedly delivered in decisive matches, most notably defeating Gladion’s Lycanroc during the Manalo Conference Final.

It also earned major victories against powerful Trainers such as Nanu and Olivia, establishing itself as Ash’s true ace in Alola.

Why Pikachu Remains Ash’s Greatest Pokémon

Every region introduced a standout partner, but Pikachu remains unmatched across Ash’s entire career. Its longevity, consistency, and list of accomplishments are unparalleled. Pikachu has defeated Gym Leaders, Elite Four-level opponents, Champions, Ultra Beasts, Mythical Pokémon, and even Legendary Pokémon while remaining Ash’s closest companion from his very first journey.

Most importantly, Pikachu delivered the defining victory of Ash’s career by defeating Leon’s Charizard, securing the Masters Eight World Championship and fulfilling Ash’s lifelong dream.

For many fans, while Pokémon like Greninja, Infernape, and Sceptile may each represent the peak of a specific era, Pikachu will always be Ash Ketchum’s greatest and strongest partner.

Sources: Gamek