With the Pokémon franchise celebrating its 25th anniversary in 2021, let's take a look back on Ash Ketchum's journey to find the anime's 25 best episodes. Only one episode will be chosen from multi-part storylines, and episodes from side series that don't share a universe with the main series, like Originswill not be considered. Here then, in no particular order, are our picks for the 25 best episodes of the Pokémon anime (so far).

Season 5, Episode 60, "Can't Beat the Heat"

Gary Oak and Blastoise Pokemon Animated Series

No rival has been more memorable for Ash than the highly abrasive, overly competent Gary, yet it's not until Johto's Silver Conference that the two finally have a full six-on-six battle. Seeing Ash's Charizard defeat Gary's Blastoise in spite of a type disadvantage and Ash's hard work to surpass his rival pay off makes it the highlight of the Johto League.

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Season 1, Episode 14, "Electric Shock Showdown"

Pokemon Electric Shock Showdown Raichu Pikachu Lt Surge Ash

One of the series' fundamental episodes, this was the first time Ash ever truly earned a gym badge on his own merits, fairly fighting a leader who wasn't one of his traveling companions. The episode establishes Ash's training style as one of respect, as he leaves the choice to evolve in Pikachu's paws, while simultaneously showing Pikachu to be a hardworking Pokémon who refuses to take the easy way to strength, instead choosing to train and work harder to earn it.

Season 13, Episode 31 "Battling a Thaw in Relations!"

While Ash's match against Tobias's Darkrai was nail-biting, it's his fight against Paul that is the most meaningful during the Sinnoh league. Having fought with Paul in both battles and ideals throughout the season, Ash is desperate to show Paul that Pokémon aren't just things to be used but creatures with minds of their own. There's no better way to show that than defeating him with the Infernape Paul released as a Chimchar for being too weak. Not only does this bring closure for Infernape, but it finally proves that Ash's training methods really are the better style.

Season 9, Episode 12, "Time-Warp Heals All Wounds"

May may have broken the universe with this episode -- and that's part of why it's one of the best in the series. When May finds herself, her Squirtle and Meowth mysteriously transported to the past, she immediately commits the cardinal sin of time traveling and changes things, using Squirtle's Ice Beam to cause snow instead of rain, drastically altering history. When she returns to the present, the city is completely changed for the better -- although her friends somehow seem completely unchanged, letting her slip right back into her journey.

Season 2, Episode 6, "The Misty Mermaid"

With its unique underwater twist, the Misty Mermaid is an absolute treat for the eyes. The ballet gives everyone (even Team Rocket) an excuse to dress up while fleshing out Misty's relationship with her sisters and showing what's been happening to the Cerulean Gym in her absence. The unique plot of having to alter the ballet on the fly to account for Team Rocket attempting to steal all the Pokémon actors shows not the gang's ability to act under pressure (literally).

Season 2, Episode 49, "Charizard Chills"

No Pokémon had such a memorable impact on the series than Charizard, whose famous rebellion finally came to an end in this episode, finishing an arc over 50 episodes in the making. Ash's dedication to helping Charizard warm back up, even to detriment of his own health finally earns the lizard's respect, making it an emotional and satisfying episode for anyone who's been following Charizard's journey since he was first rescued in Season 1, Episode 11, "The Stray Charmander."

Season 21, Episode 12, "The Professors’ New Adventure!"

Officially recognized as the 1000th episode of the series by the Pokémon Company International, the series capped off the milestone with another milestone -- Professors Kukui and Burnet's wedding. Aside from shaking up the status quo, it gives the more slice-of-life toned Sun and Moon seasons two surrogate parents for Ash. The episode pulls out all the stops to make it a true celebration, bringing characters and Pokémon from throughout Alola while also managing to find time to set up developments for future episodes, such as the first appearance of Poipole and Faba's reformation.

Season 14, Episode 26, "Scare at the Litwick Mansion!"

Pokémon is a kids' show, which makes the rare terrifying episode even more unexpected. Trapped in an abandoned mansion by a sudden storm, Ash and co. encounter a group of Litwick who at first seem to simply enjoy scaring them and aiding Team Rocket -- before it's revealed that the Litwick are actually slowly draining the life energy out of the group, intent on sending them to the Ghost World. It takes everyone -- Team Rocket included -- to take the Litwick down and escape, making it the best horror episode in the series.

Season 23, Episode 26, "Splash, Dash, and Smash for the Crown!"

Pokemon Journeys' funniest, most off-the-wall episode, really pushed the suspension of disbelief. The two stories included a Magikarp Jumping contest reminiscent of the 2017 app that ends with Goh's Magikarp in orbit and a trip to an island of Slowpoke, where Slowking's Shellder crown changes everyone's personalities. What ensues is one of the most hilarious, laugh out loud episodes the series has ever seen.

Season 8, Episode 43, "The Symbol Life"

Anime Pokemon Charizard Articuno Fight the Symbol Life

With Ash having already completed the Hoenn league, the anime was quick to move onto a new frontier -- the Battle Frontier. And no battle was quite as exciting, or dramatic as Ash's introduction to the system against Nolan and his Articuno. While using a legendary Pokémon could easily be seen as unfair, Ash retaliates by calling upon Charizard, his most overpowered Pokémon. Not only does this give him a type advantage, but it brings back a fan-favorite character for an outright brawl with one of the most elegant legendries in the region.

Season 2, Episode 16, "Go West Young Meowth"

Throughout the series, Meowth has been quite a smitten kitten, falling for various other feline Pokémon, such as May's Skitty, and Purrloin -- but his first love was by far the most impactful, as it's the reason why he speaks and walks on two feet! Framed around seeing a movie in Hollywood, this flashback episode explains the origins of our favorite villainous cat while simultaneously explaining his hatred of his species' evolved form, Persian.

Chronicles, Episode 13, "Training Daze"

Anime Pokemon Team Rocket Jessie James Meowth River Dangling Training Daze

Similar to above, this is the origin story of Team Rocket as just that -- Team Rocket. While the backstories for Jessie and James can be more muddled than a mud pie, this episode shows exactly why they're so loyal to each other, and how they ended up becoming the team we see throughout the main series, while also establishing how their rivalry with Butch and Cassidy began.

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Season 1, Episode 36, "Pikachu's Goodbye"

Pokemon Pikachu Goodbye Ash Kethum Released Pikachus Sad Original Series

Ash has always put the well-being of his Pokémon first and valued their feelings about his own -- something that this episode makes abundantly clear. When Ash and the group come across a bunch of wild Pikachu who quickly accept Ash's as one of their own, Ash prepares to say goodbye, believing it to be in Pikachu's best interests to be with his own kind -- but Pikachu won't let that slide, and refuses to leave his side.

Season 11, Episode 25, "Strategy With a Smile"

May's Glaceon versus Dawn's Piplup in the Pokémon anime.

Of all of Ash's companions, none have been so fiercely competitive as May and Dawn. Seeing these two compete against each other is both nerve-wracking and immensely satisfying. Her unexpected win tops off Dawn's character arc, finally returning the confidence she had lost 18 episodes earlier, in Season 11 Episode 9, "Team Shocker." It's clear Dawn will be making quite the name for herself as a Coordinator, while simultaneously making the Wallace Cup one of the best Contest arcs in the series.

Season 19, Episode 38, "Down to the Fiery Finish!"

Ash Greninja vs. Mega Charizard, Pokemon

Of all of Ash's league adventures, none are quite as eventful or spectacular as the Kalos League, most of all Ash's final battle with Alain. What really sets this episode apart is just how much it does in such little time while executing every story beat flawlessly. In just twenty minutes, it wraps up the league, ties in the Mega Evolution specials and acts as a transitionary episode into the final battle against Team Flare without ever losing an ounce of momentum or overwhelming the audience with constant action.

Season 21, Episode 39, "Dummy, You Shrunk the Kids!"

Alolan Persian Pokemon

The Sun and Moon era of Pokémon was well known for its smaller-scale stories, focusing more on character development and showing the main cast as kids who still had a lot to learn about the world -- but the small scale of this episode hides a big, fun adventure. After a malfunctioning machine shrinks the kids down, it's up to them to learn to navigate the now-giant world around them. The episode is full of amusing hijinks, and its cliffhanger ending with Sophocles' giantized Togedemaru leaves viewers a lot to laugh about as they imagine what happened next.

Season 8, Episode 5, "Gaining Groudon"

While its second part may be more visually spectacular with the titular legends clashing, "Gaining Groudon" lays the groundwork for the Hoenn legendaries to face off amazingly, given that the entire plot is crammed into two episodes. From the cast's capture by Team Magma to Pikachu's possession by the Blue Orb and the reappearance of Lance, there's a constant rise of tension that carries throughout the whole episode without any wasted space, leaving the audience clamoring for more. While the episode ends on a cliffhanger, it does what any good Part One should -- it makes people want to come back for Part Two.

Season 22, Episode 16, "Memories in the Mist!"

Pokemon Memories in the mist anime scene

Be prepared for waterworks with this much-beloved episode that gives Mallow something that many many people have wanted, but never been able to have -- one last conversation with her deceased mother. While the episode also ties in a reunion between Torracat and Stoutland, whose passing had shown that Pokémon was mature enough to handle death tactfully, Mallow's chance to reconcile with her mother, only to discover that she didn't need to, is the true emotional heart of the episode. It also contributes to the overarching plot by proving that Mohn, Lillie and Gladion's father who didn't appear in Tapu Fini's mist, must still be alive somewhere.

Season 6, Episode 6, "A Poached Ego"

Jessie Jame Team Rocket Pokemon Arbok-Ekans-Weezing-A-poached-ego-poacher-Wobbuffet-meowth (1)

With Team Rocket being so instrumental in the series enduring formula, viewers can't help but get attached to the lovingly hapless trio and their Pokémon -- and if there's anything Team Rocket does right, it's caring for those very Pokémon. As such, the episode where they put the well-being of their Pokémon first, rescuing their pre-evolved forms from a poacher by releasing Arbok and Weezing to protect them, helps to mark the end of an era.

Season 8, Episode 17, "Do I Hear a Ralts?"

Ralts in Pokemon anime

In a role reversal from the games, rather than sick Wally encountering and capturing a Ralts, Max finds a sick Ralts, and nurses it back to health while protecting it from Team Rocket. His perseverance hints to the type of caring trainer Max will one day become, and when he finally gets Ralts to a Pokémon center, his moment of vulnerability as he runs, crying to his sister, is a testament to how much he's come to care for the Feeling Pokémon. Capping off the emotional story is Max's promise to return and train with Ralts one day -- something many fans dream of seeing come to fruition.

Season 22, Episode 47, "Enter the Champion!"

Ash becomes the Alola League Champion, holds trophy with Pikachu on his shoulder

After over 20 years and 1000 episodes, Ash finally becomes a Regional Champion. While his exhibition match with the Masked Royal would neatly wrap up the character arcs and loose plot threads of the Alola region, nothing could be more amazing for fans than Ash's win against Gladion for the Championship. And nothing more nerve-wracking either, as Ash's win left the future of the series uncertain for the first time ever.

Season 18, Episode 12, "A Showcase Debut!"

Serena performing in a Pokemon showcase in the anime with pancham and fennekin

In the anime-original competition, viewers had no idea what to expect from Serena's first attempt to earn a Princess Key, but no one expected what happened. With Fennekin tripping on its overly long ribbon, Serena hits the first major hurdle in her journey, having finally found a path she wants to pursue -- only to fail spectacularly on her first outing. The episode ends with Serena collapsing in tears with her Pokémon before deciding to get back up and try again, this time putting everything she has into it. In perhaps the most dramatic haircutting scene ever, she returns to the group a changed and bolder girl.

Season 1, Episode 20, "Bye Bye Butterfree"

butterfree ash farewell

Pokémon knows how to hit where it hurts for the waterworks when it wants to -- and watching Ash say goodbye to Butterfree, the very first Pokémon he ever caught, is enough to make any fan tear up. While the plotline would be echoed with Jessie and her Dustox later in the Sinnoh region, "Bye Bye Butterfree" was the very first time a Pokémon had been released onscreen and the first time that viewers realized that they may have to say goodbye -- forever -- to some of Ash and co.'s most beloved Pokémon pals.

Season 5, Episode 13, "A Promise Is a Promise"

Notable for not only featuring the cutest baby Lugia, nicknamed Silver, but also multiple reoccurring characters and the ever competent Butch and Cassidy, this episode completes a three-episode arc where Team Rocket attempts to capture, then use Silver to draw out its mother, while Ash, Ritchie and the rest of the gang seek to keep their promise to reunite Silver with his mom. Not only does this allow for a rare case of seeing a young legendary Pokémon, but it shows how much a threat Team Rocket can really be.

Season 1, Episode 1, "Pokémon - I Choose You!"

The episode that started it all holds up surprisingly well, wasting no time introducing the world and Pokémon battles through Ash's enthusiasm, while simultaneously making him relatable through his indecision and oversleeping habits. The optimism, kindness and perseverance he demonstrates pay off when Pikachu finally understands that Ash just wants to be his friend -- as Ash stands, ready to sacrifice himself to protect his new buddy. Pikachu's thunder as the Spearow descend pushes the TV-Y7 rating, but cements their bond as one of mutual trust, laying the foundation for the rest of the series beautifully.

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