The Pokemon games have always varied in difficulty, especially with the changes that were made to the way that experience is shared between Pokemon in some of the series' more recent entries. In fact, the actual design of the trainers and battles within the games often have very little impact on the overall difficulty.

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Instead, most battles are made harder through level increases. However, some battles spread throughout the franchise are made incredibly difficult due to their inherent design. The difficulty of some of these battles is so high that many Pokemon fans remember these battles with a mixture of awe and fear, especially one particularly threatening Miltank from Goldenrod City.

Updated September 6, 2022, by Tom Bowen: Since it first made its debut more than a quarter of a century ago, the Pokemon series has provided players with some incredibly challenging trainer battles. Some draw their difficulty from the sheer strength of the opposing team, while others take place early on in their respective games before players have had a chance to build the diversity required to counter these terrifying trainers into their teams. With the right strategy in place, none are impossible, but some of the most difficult trainer battles in Pokemon history will take a lot more effort to overcome than others.

12 Brock

Back in the day with no access to the internet, it was very uncommon for players to actually know what moves Pokemon learned at each level on top of type advantages. Being the first Gym Leader also means that the Brock fight was probably being completed by new players who didn’t know the intricacies of type advantages.

Fighting Brock in Pokemon Yellow with a Pikachu and another small rodent from Route 1 is incredibly hard. Only a Nidorino with double-kick could reliably get players through this fight, and most people had no idea that was even an option.

Though he only has two Pokemon at his disposal in the first generation games, defeating Brock's Onix and Geodude with Pikachu as the player's main is no easy feat, as Ash discovers early on in the Pokemon anime. Thankfully, their levels are at least lowered by two in Pokemon Yellow, with Geodude falling from level 12 to level 10 and Onix being dropped to level 12 having originally been at level 14.

11 Clair

Dragon-types were harder to deal with back in the old days before Fairy-types. In the Gen 2 games of Gold, Silver, & Crystal, with only a couple Ice-types and only two Dragon-type evolutionary lines, players fighting Clair would need Pokemon capable of dealing and withstanding some serious damage. But generally, powerful Dragon-types were never Clair’s issue.

Instead, it was Clair's under-the-radar destroyer, Kingdra. Being a Water and Dragon-type, Kingdra’s only weakness was other Dragon-type moves. And with only Dratini and Horsea, players didn’t have many options. On top of this, it knows heavy-hitting moves and smokescreen, so good luck hitting the thing; for those who manage, good luck surviving Kingdra's own crazy attacks.

Clair's full lineup consists of a level 40 Kingdra as well as three Dragonairs, all of which are level 37. The former is definitely the toughest to overcome, although the Dragonairs can also cause problems if players head into the battle unprepared. They all know Slam, Dragon Breath, and Thunderwave, but their fourth slots are filled with a strong elemental attack, allowing them to dish out massive water, electric, and ice damage respectively.

10 Whitney

Anyone who played through Pokemon Crystal remembers a battle that brought a fury like no other down upon unsuspecting players within the third gym. That’s right, Whitney, the Normal-type Gym Leader. With a simple Clefairy and Miltank, Whitney brought players to their knees.

Clefairy’s Metronome could mean life or death all at the whims of fate. Miltank’s Rollout, stab damage Stomp, and Milk Drink mean that if trainers don’t take out this powerhouse quickly they can expect a thorough thrashing. To top it all off, this is still early enough in the game that players don’t have access to revives other than what they find en route, so a one-shot Rollout could be devastating.

Much like Brock in the gen 1 games, Whitney only has access to two Pokemon. As players will soon learn, however, a level 18 Clefairy and a level 20 Miltank are not to be trifled with at this stage in the game. Their normal typing makes them incredibly difficult to counter, while their well-curated move sets can cause plenty of problems for those who don't know what they're doing.

9 May/Brendan

In Pokemon Emerald, the player’s rival isn’t incredibly difficult, however, for players hoping to speedrun the game, their third battle can make or break a good time. For Emerald speedrunners, they need to get to this battle with a level 18 Marshtomp. Unfortunately, this means a double weakness to their Grass-type, Grovyle.

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Further, they will need to use stat-boosting items to make sure Marshtomp will survive and win the fight, but the only opportunity to do this is while fighting their Wingull. What makes this so difficult is that Wingull knows Supersonic and Growl, both of which can make it impossible for Marshtomp to defeat the rivals Grovyle. Ultimately, it all comes down to luck and which moves Wingull decides to use.

Like the series' many other rivals, the Pokemon that May and Brendan have at their disposal vary depending on which of the three starter Pokemon players chose. They'll always end up with a Tropius though, with two of their remaining slots being filled with any two of Ludicolo, Slugma, and Pelipper. Their final Pokemon will be the starter that's strong against the player's own starter, which can often cause problems for those players who fail to diversify their collection of Pokemon.

8 Red

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One of the hardest fights in any Pokemon game is the climactic battle at the end of Pokemon HeartGold and SoulSilver. Fighting Red is a surprising challenge that many players assume they’re ready for before spending the time to really research this intense challenge.

Red’s team is such a threat because of its insanely high level. With Pokemon between levels 80 and 90, trainers will need to grind (even after beating all of the Kanto gyms) before they’re ready to take on this difficult fight.

As well as owning all three of the gen 1 starter Pokemon at level 84 and in their final evolutionary forms, Red also has access to a level 80 Lapras, a level 82 Snorlax, and a level 88 Pikachu. As such, countering him will require a team with a lot of type diversity, not to mention one that consists of Pokemon with similarly high levels.

7 Cynthia

In most Pokemon games, the champion of the region is meant to be the game’s most difficult fight, but this doesn't always end up being the case. Well, Pokemon Platinum is one of the very few games in the series that definitely gets this right.

With a team not dedicated to any one type, and the most powerful Pokemon of this generation in Garchomp, Lucario, Spiritomb, and Togekiss, players really need to watch their backs. Additionally, Cynthia’s team is at a very high level, with her Garchomp maxing out at level 78. Overall, her team is just really really good.

As well as Garchomp, Lucario, Spiritomb, and Togekiss, Cynthia also has access to a Roserade and a Milotic. All of her team are at least level 74 by the end of the game, meaning that players will have to level their own Pokemon up quite a bit if they're to have any chance of beating her again after Stark Mountain.

6 Ghetsis

Ghetsis’ party in Pokemon Black and White is one of the hardest team fights in the franchise. With a generally powerful team that uses real strategies, Ghetsis makes many players quiver. His Eelektross has no weaknesses, his Cofragigus effectively stalls, his Seismitoad can only be stopped by Grass-types, and his Bisharp can only be countered by a solid Fighting-type.

The real kickers are his Hydreigon and his Bouffalant. The latter has incredibly powerful attacks and needs to be stopped quickly before it wrecks an entire team, but Hydreigon is an absolute monster. With incredible speed and devastating type coverage, this evil dragon is sure to leave a bad taste in any player’s mouth.

With the exception of his Hydreigon, which is level 54, all of Ghetsis' Pokemon are level 52. Together they boast ridiculously good type coverage, with the six of them representing eight of the series' 18 different types when dual-typing is taken into account.

5 Evice

The final boss of Pokemon Colosseum is one of the hardest fights in the franchise's history. With a 10-level jump from the fight that immediately precedes this boss battle, Evice is one bad man. Additionally, his team absolutely slaps.

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With an Intimidate Salamence, a nearly indestructible Scizor, a Machamp with Rockslide and Earthquake, and a Slaking and Slowking that make an absolutely deadly combo with Skill Swap allowing the beefy sloth to attack every turn, Evice makes many trainers cry. Further, with an incredibly limited selection of Pokemon throughout the game, this battle is extremely tough.

All of Evice's Pokemon are between levels 60 and 62 and each one boasts a different elemental type. As well as the aforementioned Pokemon, he also has access to an Aggron, though it will probably be Salamance and Slaking, both of which are level 60, that will cause players the most trouble.

4 Ardos & Eldes

These bad blue and red brothers from Pokemon XD: Gale of Darkness are two of the hardest fights in the franchise's history. Because they’re about the same though, they can just be lumped together.

What makes them so difficult is how Shadow Pokemon work in this game. With improved Shadow-type moves that are super effective against all non-Shadow-types and teams with 4 Shadow Pokemon each, they really just make battles into a living hell. And worst of all, players are expected to catch their shadow Pokéemon, meaning they need to stall through super powerful attacks hoping they can survive just long enough to put all of them away.

Between them, they have access to the likes of Sceptile, Charizard, Gengar, Metagross, Latias, and Snorlax, making them incredibly difficult to beat. Worse still, in Colosseum battles, they'll have access to six different Pokemon despite only actually using four, meaning that players will have to plan for all eventualities when selecting their own team.

3 Valerie

Valerie raising her arms in the Pokemon anime

The introduction of Fairy-type Pokemon in Pokemon X & Y took a lot of players by surprise. Not only was it the first new Pokemon type in more than a decade, but it also presented several unique challenges, most notably, understanding how exactly Fairy-type Pokemon would interact with some of the other dual-type creatures found throughout the games.

Laverre City Gym leader Valerie was more than ready to capitalize on this confusion, with many players needing multiple attempts to get their hands on the Fairy Badge. Just for good measure, her final Battle Chateau rematch was considerably harder, not just due to the high levels of her Pokemon, but also due to how few viable counters there were for them in the sixth-generation Pokemon games.

In the gym battle, Valerie only has three Pokemon on her team, though two of them being dual-types can make beating them surprisingly difficult. Even if players do find a way to take care of Mawile and Mr. Mime, her Level 42 Sylveon has the potential to flip the battle on its head, with its high Special stats combining with Dazzling Gleam to devastating effect.

2 Greevil

The final boss battle in Pokemon XD: Gale of Darkness is even harder than the two brothers before. With 6 Shadow Pokemon that bring massive super effective damage against all non-Shadow-types, trainers need to sustain a team for a long time.

Even worse is how trainers have to catch each of them before they can move on to the next Pokemon. On top of that, three of the Shadow Pokemon are the legendary birds, Articuno, Zapdos, and Moltres. With very low catch rates and devastating shadow moves of their own, these three leave any trainer questioning why they really need to catch-em-all.

Dealing with Greevil's team is a lot easier said than done, as it's both incredibly powerful and also fairly well balanced too. The Legendary Birds are undoubtedly the main attraction, but Rhydon, Exeggutor, and Tauros are no pushovers either and will require careful planning - and perhaps a little bit of luck - to successfully overcome.

1 Volo

Pokemon Legends Arceus Volo and Giratina

It's not often that players find themselves face to face with Legendary Pokemon in trainer battles. Likewise, most opponents tend to have between three and five Pokemon in their teams, with only end-game enemies filling all six of the available slots. Apparently. though, Volo didn't get this memo, as the Pokemon Legends: Arceus villain bucks both of these trends rather emphatically.

Initially, Volo is rocking a full team of six Pokemon, each of whom has been specifically chosen to counter players' counters. If players are somehow able to defeat all six, Volo will then summon Giratina, who players will need to beat in both its Altered and Origin Formes. This effectively means that trainers will need to defeat eight Pokemon with their team of six, with no opportunities to heal before facing off against Giratina.

What makes this battle all the more difficult is how little attention Pokemon Legends: Arceus pays to trainer battles. There are only a handful of them in the game, with players instead encouraged to catch new Pokemon rather than trying to build and train a competitive team. The game's many Mythical and Legendary Pokemon can help in this regard, but most players will likely need a few attempts to beat Volo and Giratina nonetheless.

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