Since premiering in Japan on April 1, 1997, over 1139 episodes have aired as part of the official Pokémon anime. Following Ash Ketchum on his never-ending quest to catch-em-all and become a Pokémon Master, the series has followed this plucky 10-year-old and his myriad of companions as they’ve traveled to numerous regions and had a tonne of adventures.

Whilst the majority of these adventures are fun and exciting, such as battling against Gyms or meeting Legendary Pokémon, a select few are rather sad. Indeed, despite the show being ostensibly made for children, a few episodes have ventured into dark territory, offering some depressing themes and heart-breaking events. Although it would take too long to highlight every sad episode (there have been over 1100 regular episodes – there are likely hundreds of sad ones), here are a few that are truly a cut above the rest, bound to make even the most hardened Pokémon master shed a tear.

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Bye Bye Butterfree

Ash and Butterfree

The 21st episode of the first season, Bye Bye Butterfree first aired in Japan on August 19, 1997 and in the United States on October 5, 1998, and it likely the cause of many a childhood trauma. Often pointed to as one of the saddest episodes in all of anime, not just Pokémon, Bye Bye Butterfree offers an interesting premise: despite wanting to catch them all, can Ash say goodbye?

The episode begins with Ash and the gang noticing a large flock of Butterfree on the horizon – turns out, this is part of this breed of Pokémon’s “season of love celebration”, in which they find a mate. Ash sends out his Butterfree to mingle, and they promptly fall in love with a pink Butterfree. After an episode’s worth of hijinks (including the requisite interference from Team Rocket), Butterfree eventually decides to leave to mate with this Pink alternate, meaning he has to say goodbye to Ash. With a teary farewell, Ash sets his Butterfree free, watching as the first wild Pokémon he ever caught flies away into the sunset; tear-jerking stuff.

Charmander - The Stray Pokémon

Another tear-inducing classic from the original series, Charmander – The Stray Pokémon is the 11th episode of the anime and was first aired in Japan on June 10, 1997 and in the United States on September 22, 1998. Although the series so far featured trainers who loved and cared for their Pokémon, this episode showed what happened when this wasn’t the case.

On their way to Vermillion City, the gang discover an adorable Charmander sitting on a rock. Ash tries to catch this rare Pokémon, but is stopped when it’s revealed that Charmander belongs to someone else; he’s waiting for a trainer named Damian. However, when Damian arrives, it’s revealed that he purposefully abandoned Charmander due to it being “so weak.” However, a dutiful Pokémon, Charmander refuses to relent waiting, even when being attacked by a group of Spearow or almost killed in the rain. Eventually, with Pikachu’s help, Charmander sees the error of his ways, rejects Damian, and joins the much-kinder Ash, eventually evolving into Charizard and becoming the powerhouse of the 10-year-old’s team.

Mewtwo Strikes Back

Also known as Pokémon: The First Movie, Mewtwo Strikes Back was the first feature-length film set in-canon with the Pokémon anime. Debuting in Japanese theatres on July 18, 1998, and then making its way to North American theatres on November 12, 1999, the film was a critical and commercial success… although was also a bit of a tear-jerker as well.

In the movie, Ash and co are invited by a mysterious letter to visit a mansion on a distant isle – when they get there, they discover they were invited by the bitter and maniacal Mewtwo; a failed attempt to clone the Legendary Pokémon Mew. Engaging in battle with the assembled trainers, Mewtwo sends out cloned Pokémon, who quickly get the upper-hand on the gang. During the battle, in an attempt to save Pikachu from an attack, Ash is turned to stone. Shocked that his best friend and loving trainer is seemingly dead, Pikachu begins to cry: an earnest show of emotion that is soon copied by every Pokémon present. Magically, through these tears, Ash is brought back to life, and Mewtwo (moved by this show of emotion) resolves to work with trainers instead.

Seeking Shelter from the Storm

From the XY era of the Pokémon series, Seeking Shelter from the Storm is the 813th episode of the Pokémon anime, first airing in Japan on January 30, 2014 and in the United States on April 19, 2014. As established, the Pokémon anime is primarily made for children, so rarely deals with themes of loss (or, if they do, the trainers/Pokémon are quickly bought back to life). For this sad episode, this was not the case.

Due to a thunderstorm, Ash and the gang seek shelter from the weather in a mansion. Initially thinking this abandoned house is haunted due to loud cries and ominous goings-on, they soon discover that it’s just the Pokémon Espurr biding time. Turns out, Espurr used to be best friends with the old lady who lived there ever since she was a child, but now the octogenarian had gone missing. Unfortunately, it is revealed that the old lady had died, leaving Espurr waiting for no one. In a moving final scene, Espurr joins the old lady’s granddaughter as they drive to put a flower on the lady’s grave – a poetic image, especially for a Pokémon episode.

Glory Blaze!

Pokémon

Set in the Diamond and Pearl era of the anime, Glory Blaze! is the 517th episode, and it’s more upsetting than sad. First airing in Japan on October 18, 2007 and in the United States on February 1, 2008, the episode reveals the lengths some trainers will go to win a Pokémon battle.

The episode begins with Ash and team entering in the Hearthome City Tag Battle Competition, and Ash is paired with Paul; a rival trainer who uses a Chimchar. Through the tag battles he and Paul fight together, Ash notices that Paul is increasingly tough on his Chimchar, being verbally abusive and demanding that the Pokémon doesn’t dodge attacks and instead allows itself to be hit.

Spying on Paul one evening, Ash discovers that the trainer routinely lets all his other Pokémon attack Chimchar as ‘practice,’ in an attempt to trigger Chimchar’s Blaze ability (it boosts a fire Pokémon’s attacks when it’s at low health). Disgusted by what he sees, Ash confronts Paul, and Chimchar joins Ash instead, eventually evolving into an Infernape and beating Paul in battle. While not sad, per se, the episode is a depressing and upsetting reminder that, even in the fun world of the Pokémon anime, some trainers really do take it too far.

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