The pocket monster phenomenon has generated over 20 seasons of television that are the picture of nostalgia for everyone, from millennial to gen Z. From the day Ash Ketchum stole Misty's bike to save his sassy but precious Pikachu, audiences have been hooked on the creatures, their trainers and the wacky adventures that take them all across the Pokémon world.

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However, with some seasons having more than 50 episodes, there were sure to be some duds. Many episodes from the original seasons and, surprisingly, from the newest seasons have high scores in the IMDb ratings but towards the middle, the iconic show saw a definite dip in positive reviews. The majority of the lowest-rated episodes on IMDb are episodes released only in Japan with no English dub. The episodes depicted in this article are all American-released episodes. Here are the most poorly rated episodes of the long-running classic and why they rated so low.

10 Teaching The Student Teacher: Season 13, Episode 10 - 5.1/10

This episode is a part of the PokemonDiamond and Pearl: Sinnoh League Victors series. It is a miracle the episodes in these series were not lowly rated just for the number of names in the series title.

This episode is one of several poorly reviewed episodes to feature Piplup, a penguin-like Pokémon, who was the victim of an amateur Pokemon trainer's tricks in this episode. Pokemon trainer extraordinaire Dawn, Ash and Brock find themselves teaching youngsters how to handle their Pokemon but also how to express their emotions. Whether reviewers do not like Piplup or just do not like to see Piplup hurt, the world may never know.

9 The Lonely Snover: Season 12, Episode 16 - 5.1/10

The vast majority of low rated Pokemon episodes on IMDb come from the four seasons of Diamond and Pearl (seasons 10-13). "The Lonely Snover" occurs in the Galactic Battles section of DP and follows the rescue of an initially hostile Snover.

The Snover starts his soon-to-be long term friendship with the main characters by freezing them, tripping them and putting them to sleep. Upon waking up, the characters realize the Pokemon has a lot to offer and go through great tribulations to save him from Team Rocket's many usual attempts to kidnap the Pokemon. The episode is more like a re-make of Misery than Pokemon but, in the end, Kathy Bates gets her way.

8 Piplup, Up And Away: Season 13, Episode 7 - 5/10

This episode also features the curiously despised Piplup. In this episode, poor Piplup continuously gets hurt during another Pokemon's training. Feeling dejected, the Piplup takes off on his own and is eventually turned into a double agent by Team Rocket.

Team Rocket convinces the emotionally devastated Pokemon to turn on Pikachu causing the only Pokemon to be the main character to almost get kidnapped yet again. Piplup also finds himself kidnapped and, in his anger, learns a new move. Despite the destructive results of his actions, the Pokemon sees no punishment and continues on with his friends. Reviewers cried for justice for Pikachu by making this episode one of the lowest-rated in the show's history.

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7 Beating The Bustle and Hustle: Season 12, Episode 30 - 5/10

Now in Lilypad Town, the group of heroes comes upon yet another massive Pokemon tournament. The heroes compete and, big surprise, win battle after battle. Most audiences could predict, of course, that the tournament is masterminded by Team Rocket to steal Pokemon.

Then a weird occurrence of Pokemon stealing inception occurs where two Pokemon stealing friends snatch all the Pokemon right out from under Team Rocket's nose. Finally, it turns out Officer Jenny was there the whole time. She arrests the new bandits and sends Team Rocket blasting off again. All the many twists and turns of the episode could not stop IMDb from giving the episode one of the worst reviews of all Pokemon episodes.

6 The Brockster Is In: Season 13, Episode 33 - 4.9/10

The less than 50% rating on this episode is almost immediately explained by the creator's use of the term "The Brockster" in the title. Mixed with the episode being from DP, no further explanation is really required.

In this episode, several Pokemon on a ferry ride the heroes are taking get poisoned by a pissed off Tentacruel chasing Team Rocket. Team Rocket, the ferry riders, and the heroes must work together to save the poisoned Pocket Monsters. Brock emerges as a leader and mighty healer to the point that his Happiny becomes a Chansey. Ultimately, throughout the episode, the heroes accept the fact that soon they will be parting ways. Saying goodbye to Brock just proved too much for audiences.

5 Bibarel Gnaws Best: Season 11, Episode 5 - 4.9/10

Featuring some frequent Pokemon cliches, in this episode, the team comes across a problem only they can solve, a hardworking female stoneworker for Brock to fall madly in love with and a Pokemon attempting to communicate but unable to. On their trip towards Solaceon Town, the group comes upon an unfinished bridge that has hit a bump in construction due to the Bibarel refusing to cut more stone.

This episode was a part of the Pokemon The Series: Diamond and Pearl: Battle Dimension, a series of seasons in the show that created many negative reviews, if solely due to the excessive number of colons used in the title.

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4 The Elektrike Company: Season 10, Episode 48 - 4.7/10

In this episode, there are a little bit of all the past causes for a badly rated episode. A Pokemon zaps Ash randomly and with no consequences. Piplup is there. The episode is in the beginning seasons of DP. 

However, audiences also see a differing side of Team Rocket when they literally volunteer to repetitively zapped by Elektrike to help it train. The only clear thinking member of Team Rocket at this point is Jessie who slips in during her team's unplanned distraction to steal Pikachu. Ultimately, they are blasted off again and Elektrike becomes Manetric.  So, while the episode remains one of the worst-reviewed, all is right in Pokemon world.

3 The Psyduck Stops Here: Season 11, Episode 35 - 4.7/10

In this DP episode, the team is stopped by a set of Psyduck blocking the path. The Psyduck are aggressive and do not hear any negotiations (especially from a Piplup). It is discovered that they are guarding the pass because there is a family of Psyducks nursing some eggs that are right on the verge of hatching. On top of this, they have made a home in a nearby pond rather than their own Psyduck Lake which has been taken over by Muk. The heroes displace the Muk into a pile of female Muk and make good with the Psyduck by helping them to defeat Team Rocket.

The low rating is probably due to Brock's singing and dancing to distract the Psyduck. Not to mention, the weird sensual situation between all the Muks at the end.

2 Bucking The Treasure Trend: Season 13, Episode 24 - 4.5/10

In this second from the worst episode, the trio joins up with Buck and his Baltoy to treasure hunt. And, naturally, where there is mighty treasure there is Team Rocket trying to steal it. By the end of the episode, the heroes have been completely derailed from what they are actually trying to achieve, Team Rocket has blasted off (naturally) and the treasure is discovered to be archeological rather than monetary.

The only new element in this episode is the addition of Buck, a character who led them across the country in hopes of finding "treasure" just to reveal he is thrilled that it is just some pots. While they are happy for him taking his first steps towards an archaeology career, that information would have been really nice to start with before an hours-long journey.

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1 Down To The Fiery Finish: Season 19, Episode 38 - 4.0/10

This episode is the only episode on the whole list to come from a season other than DP. This XYZ episode is the lowest rated Pokemon episode and is nestled among episodes otherwise highly regarded by IMDb. The episode stars Pikachu and Mega Charizard X being wielded by Ash and Alain in the final battle of the Kalos League.

The major plot point is the defeat of Pikachu at the demise of Charizard's fiery breath and, overall, the defeat of Ash in the Kalos league. This leads Alain, Ash's bullheaded and aggressive rival, to be the winner even in the wake of a new disaster. Audiences watch for 19 seasons just to see another "wanna catch 'em all" champion take the gold?! Ash's defeat was not taken well.

NEXT: Pokemon: The 10 Best and Worst From Generation One