Marking the 25th anniversary of the Pokémon anime, the Pokémon Company International recently announced that the new season, Pokémon Master Journeys: The Series, will debut this summer.

Another fun snippet teases that the new season will feature “returning rivals” joining current duo, Ash and Goh. Part of what makes Pokémon adventures so fun is how trainers face off against fated foes throughout their journey. Many trainers have come and gone in the anime over the years, along with their opposing rivals. Who could these returning trainers be? Here are some fan-favorite rivals who would make excellent appearances in the new series.

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Gary Oak, Ash's Very First Rival

Ash Ketchum has encountered many rivals since embarking on his Pokémon escapades, but few measure up to his very first: Gary Oak. Both Ash and Gary grew up in Pallet Town, so their origin stories quite literally happened side by side. As his last name implies, Gary is the grandson of Professor Oak, the Pokémon researcher who gave Ash his first Pokémon, Pikachu.

Gary is Ash’s OG antagonist, never missing a chance to show him up, embarrass him, or call him inferior. All anime watchers who also played the Gameboy Pokémon games instantly understood Ash’s connection to Gary, the smug rival whom many players nicknamed something foul. Gary picks up the Pokémon catching ability quickly, having 30 by the time Ash managed to catch one. He also flaunts his fan club and gains badges faster than Ash, which makes it all-too satisfying when Ash beats Gary in a battle.

Gary Oak is actually one of the few characters besides Ash and Goh who’s already confirmed to return to Pokémon Master Journeys. His last appearance in the anime was in Pokémon the Series: Diamond and Pearl, so the classic rival will be welcomed back to torment Ash once again.

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Paul, The Harsh Pokémon Trainer

Introduced in Pokémon the Series: Diamond and Pearl, Paul is from the Sinnoh region and is the second major rival pitted against Ash. Instead of having a childhood rivalry like Gary, Paul presents a conflicting Pokémon training ideology that clashes with Ash’s training methods. The harsh trainer shows how he only cares for a Pokémon’s power and even discards them if he deems them weak. Ash, on the other hand, believes in the power of Pokémon friendship and knows that treating them with kindness is key.

The bitter rivalry between these two trainers carries throughout the season, consistently challenging each other in Pokémon battles and philosophy. Paul often criticizes Ash, calling him “pathetic,” but Ash never changes his ways and even ends up adopting Paul’s discarded Chimchar.

It’d be interesting to see what kind of role Paul would play in the upcoming series – especially if he’s changed his ways or if he finally sees consequences for his blatant Pokémon abuse. The trainer only made an appearance in the Diamond and Pearl season, so his return would be quite the reunion.

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Ritchie, Ash's Friendliest Rival

Perhaps one of Ash’s oldest and most pleasant rivals is Ritchie, who also has a Pikachu named Sparky by his side. The two start out as competitive trainers who team up to stop Team Rocket from kidnapping their Pokémon, but soon afterward Ritchie battles Ash at the Indigo Plateau. Unlike other rivals, Ritchie is kind when he wins and loses, and the two trainers encourage each other to pursue their dreams.

Introduced in Pokemon's first season, Ritchie showed up again in Gold and Silver as well as Ruby and Sapphire. As such a cheerful, supportive rival, it’d be fun to see how he’s doing now and how a battle between him and Ash might play out. Even if he just pops in for an episode or two like before, it’d be nice to see that friendly face.

Ritchie is a unique trainer, one of the few who nicknames his Pokémon. Based on his last appearance in the anime, his team consists of Sparky (Pikachu), Zippo (Charmeleon), Happy (Butterfree), Cruise (Pupitar), and Rose (Taillow). What Pokémon might be a part of his team now, and what might he nickname them?

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Team Rocket's Butch & Cassidy

pokemon butch cassidy facing off against team rocket

Villains have adversaries too, and the classic matchup between Jessie and James versus Butch and Cassidy is one of the most entertaining rivalries of the Pokémon series. Butch and Cassidy are in a similar Team Rocket agent partnership, but they are both Mid-Class Agents whereas Jessie and James are Low-Class Agents -- unsurprising considering their repeated failures.

The four agents first seriously butted heads at the Team Rocket Academy, but Jessie and Cassidy have a long history of disdainful relations since childhood. The two always seem to be at each other's necks, Jessie hating Cassidy’s snobby attitude and uppity remarks. Butch, a much less rambunctious agent, also shares a rivalry with James, who seems to have a much lower IQ than Butch.

Butch and Cassidy have been so successful on missions that Giovanni places a lot of trust in them, a fact that infuriates Jessie and James. What business might they be up to now? Seeing the familiar rivalry resurface would be a blast, even if it’s just to watch everyone mispronounce Butch’s name endlessly.

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Team Rocket's Meowth Vs. Giovanni's Persian

pokemon Meowth jealous of Persian

Rivalries between Pokémon can’t be excluded from this list, and one of the most notable is between Team Rocket’s Meowth and Giovanni’s Persian – especially with Meowth’s chatterbox one-sided dialogue providing some comic relief. Meowth is especially jealous of Persian because, according to stories, he used to be Giovanni’s favorite.

It should be mentioned that Pikachu versus Raichu, two Pokémon similarly matched by their evolved forms, fits here as well. While many Pokémon have established fated foes with other Pokémon of the same type or simply hold grudges after a lost battle, evolutionary rivals are the most memorable and therefore, the most deserving of a revival in Master Journeys.

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