With over 20 movies and multiple animated series, Ash Ketchum had plenty of opportunities to catch a legendary Pokémon. Despite the fact that he encountered nearly every known legendary Pokémon in the series, he has failed to ever tame one. Often, this is because there is some villainous force that wants to exploit the power of the Pokémon without any regard for its well-being.

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Ash is the one who stops the villains and choosing to let the legendary Pokémon enjoy their freedom makes him a much better person in comparison. However, he has befriended most of the legendary Pokémon he has met, making it odd that he seldom asks them to join him on his adventure — especially since his motto is to become a Pokémon master who plans to catch every type of Pokémon there is.

Updated on December 29th, 2022 by Brittanie Maldonado: As Ash Ketchum's never-ending quest to catch 'em all continues into the 2020s, the iconic Pokémon trainer is still running into legendary Pokémon on a regular basis. Whereas many people would attempt to tame these rare creatures, Ash has shown time and time again that he would much rather allow them to maintain their independence. This list has been updated with even more legendary Pokémon that Ash hasn't caught.

15 Solgaleo Never Technically Became One Of Ash's Pokémon

Pokémon The Series: Sun & Moon

cosmoem and solgaleo in pokemon sun and moon

During Ash Ketchum's travels throughout the Alola Region, he encounters a strange, nebulous Pokémon known as Cosmog. Perhaps due to its peculiar nature, he never officially catches this Pokémon, instead allowing it to accompany him and his friends from that point on.

Eventually, the Cosmog — nicknamed "Nebby" by Lillie — evolves, revealing itself to be a legendary Pokémon that would eventually transform into Solgaleo. This lionesque creature plays a pivotal role in the events of the anime series, but after its climactic battle against Necrozma, it departs from Ash's company.

14 Tapu Koko Preferred To Stay & Protect Melemele Island

Pokémon The Series: Sun & Moon

Tapu Koko in the Sun and Moon anime

The Alola Region is inspired by Hawaii, and as a result, it is composed of several islands that combine to form a tropical archipelago. Each of its islands is protected by a legendary Pokémon, including one that Ash Ketchum encounters several times: Tapu Koko.

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Tapu Koko guards Melemele Island, which puts it in the perfect position to watch over Ash's actions. It obviously takes a liking to the trainer, but despite having numerous friendly interactions with the Pokémon, Ash never attempts to capture Tapu Koko due to the vital role it plays for Melemele Island.

13 Regirock, Regice, & Registeel Gave Ash Their Stamp Of Approval

Pokémon: Lucario & The Mystery Of Mew

Pyramid King Brandon and his Registeel, Regirock, and Regice in Pokémon

Ash Ketchum has a long history of encountering legendary trios, so his run-in with the Regirock-Regice-Registeel group shouldn't come as a surprise. The group serves as guardians of the Tree of Beginning, which Ash and his friends encounter during the events of Lucario and the Mystery of Mew.

After a brief skirmish, the Tree's protectors decide that Ash and his friends have no intention of harming the Tree of Beginning. Despite their approval, Ash never contemplates trying to catch them, proving that he understands the importance of the task they are conducting.

12 Keldeo Remained A Part Of The Sword Of Justice

Pokémon: Kyurem VS. The Sword Of Justice

keldeo from pokemon black & white

In Kyurem VS. The Sword Of Justice, Ash Ketchum is introduced to a quartet of Pokémon that protect other creatures from losing their homes to human expansion. In particular, Keldeo (the youngest of the quartet) spends a large amount of time with the series' protagonist.

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Ash assists Keldeo as they work together to stop Kyurem, and at one point, the trainer even helps push Keldeo to its final evolutionary form. As expected, the two go separate ways after the film's conclusion, leaving fans to wonder about what the pair could have accomplished had they stayed together.

11 Victini & Ash Share An Innate Desire For Freedom

Pokémon The Movie: Black—Victini & Reshiram / Pokémon The Movie: White—Victini & Zekrom

Victini in Pokemon Movie 14

Rarely does Ash Ketchum have two opportunities to catch a legendary Pokémon, but that is exactly the case when it comes to Victini, the Fire/Psychic type introduced in Generation V. The Pokémon plays a vital role in both versions of the franchise's fourteenth film, assisting Ash after he frees it from its bindings.

After helping Ash resolve the primary conflict of each film, Victini and his new friends travel together for quite some time. Eventually, Ash's nature wins out and he parts ways with the legendary Pokémon so that it can pursue the one thing it has always wanted: freedom.

10 Ho-Oh Gave Ash Its Feather, But He'd Rather Fight It Than Catch It

Pokémon: Indigo League / Pokémon: I Choose You!

Ho-Oh flies in the sky

In both Pokémon: Indigo League and Pokémon: I Choose You!, Ash chooses not to capture the very first legendary Pokémon that he saw on his adventure. In the anime, Ash does not focus on finding Ho-Oh, contrary to the excitement he expressed when he considered meeting it.

However, in the movie, Ash does go out of his way to seek the Pokémon out. Ho-Oh gave him a feather early in his Pokémon career, which provided the primary focus of his adventure. Still, his main interest is to fight it, rather than capture it.

9 Volcanion Had A Device That Dragged Ash Around

Pokémon: Volcanion & The Mechanical Marvel

Volcanion prepares a water attack

In Pokémon: Volcanion and The Mechanical Marvel, Ash has no opportunity to capture the legendary Pokémon for half of the movie. This is thanks to the devices placed on Volcanion's leg and around Ash's waist.

Whenever they are a certain distance apart, Ash is forcefully propelled to the other device, meaning that the legendary Pokémon was literally dragging the trainer along wherever it went. Volcanion is also one of the few Pokémon that can speak the human language, and it spends most of its time voicing its distrust toward humans.

8 Magearna Couldn't Be Ripped Away From Volcanion

Pokémon: Volcanion & The Mechanical Marvel

Pokémon Magearna looks up

Another legendary Pokémon featured in Pokémon: Volcanion and The Mechanical Marvel, Magearna is a kind and thoughtful creature. It has developed a close bond with Volcanion and the other Pokémon that it lives with, as evidenced throughout the film.

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Volcanion spends the entire movie trying to protect or save Magearna, even if it means putting itself in danger. Someone like Ash would never consider pulling the two apart, especially since Volcanion proved to be the only one who could revive Magearna from its broken heart.

7 Mewtwo Distrusted Humans & Erased Ash's Memories

Pokémon: Mewtwo Strikes Back

Mewtwo uses a psychic move

Mewtwo distrusts humans more than any other Pokémon, and for good reason. After its creation, Mewtwo was tricked into working as Giovanni's weapon. Angered by the fact that he was being used as a clone of Mew, he created an army of clones free from the slavery that captured Pokémon experienced.

Although it finally saw the good in people in the events of Pokémon: Mewtwo Strikes Back, it still chose to erase the memories of the humans he came into contact with. This included Ash, because Mewtwo felt he and his comrades would be safer that way.

6 Raikou Didn't Stick Around Long Enough To Be Caught

Pokémon: I Choose You!

Raikou stands with Suicune in Pokemon

Unlike the other two legendary dogs, Suicune and Entei, Raikou hasn't seen nearly as much screentime in the Pokémon anime. It is briefly featured in Pokémon: I Choose You! when Ash, Sorrel, and Verity encounter it on Mount Tensei after meeting Entei and Suicune.

True to the nature of the legendary dogs, Raikou does not stick around for long, quickly disappearing after giving the protagonists a few seconds to admire it. Ash didn't react quickly enough to even consider catching it, and as a result, he is still without any of the Johto legendary tro.

5 Lugia Couldn't Be Caught Without Severe Consequences

Pokémon 2000

Lugia carries Ash and Pikachu on its back

When Pokémon 2000's villain captured Moltres, Articuno, and Zapdos, the whole world's climate started changing for the worse. They were eventually freed by Ash and his friends, but the birds decided to fight each other in a cataclysmic battle. This battle could only be stopped by the combined efforts of Lugia and Ash, who was the chosen one from prophecy.

Restoring balance was Ash's priority, but after seeing the consequences of catching a legendary Pokémon, Ash was convinced not to do the same. However, that doesn't mean the pair didn't form a fantastic bond during their time together.

4 Jirachi Was Closer To Max Than Ash

Pokémon: Jirachi—Wish Master

Jirachi smiles happily in Pokemon

Jirachi would not have particularly liked being caught by Ash in Pokémon: Jirachi—Wish Maker. The Pokémon is only able to stay awake for seven days when the Millennium comet appears in the sky. Its manifestation also requires a best friend, chosen by destiny, to be nearby.

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In the film, this friend happens to be May's brother, Max. These two characters got attached to each other quickly, and Max was particularly sensitive about his limited time with Jirachi since it had to sleep for another thousand years once the comet disappeared. It would have been cruel for Ash to catch it.

3 Celebi's Revival Was More Important To Ash Than Catching It

Pokémon: 4ever

Celebi floats in the forest in Pokemon 4Ever

When Ash met Celebi in Pokémon: 4ever, it was terrified since it was being pursued by a poacher called the Iron-Masked Marauder. Both Ash and Sam, the trainer from 40 years in the past who Celebi brought to the future, took time to slowly bond with it. Unfortunately, it wasn't long before the poacher caught Celebi with a dark ball, which forcibly turned Celebi into a monster.

The overuse of its powers ended up killing Celebi before other Celebi traveled through time to save it. Ash seemed more glad about it being revived than concerned about catching it. Additionally, Celebi had to take Sam back to his own time period, so Ash forever lost his chance to catch this unique Pokémon.

2 Rayquaza Was Too Powerful & Destructive For Ash To Bother Catching

Pokémon: Destiny Deoxys

Rayquaza floats in the sky

When Rayquaza attacked LaRousse City In Pokémon: Destiny Deoxys, it destroyed a huge portion of the city in its rage. It has proven itself to be very territorial as it didn't hesitate to attack Deoxys after recognizing that it wasn't from the same planet, exhibiting a temperament that doesn't lend itself to being part of a team.

Most of the time, Rayquaza keeps to itself and stays in the ozone layer where no one is able to bother it. This, coupled with the fact that it was so powerful and destructive, kept Ash from even thinking about catching it in the midst of all the chaos.

1 Latias & Latios Need To Remain Free To Protect Their City

Pokémon Heroes: Latios & Latias

Latias and Latios fly together

Both Latias and Latios were guardians of Alto Mare City that would protect the city if it was ever in danger. Latias appears in front of Ash in Pokémon Heroes: Latios & Latias disguised as a girl, so his first instinct wasn't to assume that she was a Pokémon.

Eventually, Ash helps the legendary Pokémon when they are pursued by members of Team Rocket. However, he doesn't catch them because of their role as guardians. On top of this, Latios also gives its life while protecting the city, making it even more unlikely that either of them would join Ash on his adventures.

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