The Pokémon mainline series wouldn't be the same without gym battles. They test players' skills before they can progress in the game. At every turn, the Pokémon's developers are shifting the battles' dynamics to bring a new experience. Each gym battle might be turn-based, but things like two-on-two battles, Mega Evolutions, and Dynamaxing keep the series from going stale.

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You've already faced them, and now, it's time to see how they stack up. Let's take a stroll down memory lane and see which gym battles came out on top. Which generation of gym battles did you find the most memorable?

8 Generation IV

Generation IV of the Pokémon main series games contained Pokémon Diamond, Pearl, and Platinum. This marked one of the last generations before the main series games switched to 3D visuals. It was arguably the best generation for 2D graphics, and its gym leader battles weren't bad either. Iconic gym leader battles like Volkner, the irksome Electric-type trainer, made this generation stand out. It also contained awesome gym leaders like Candice and Crasher Wake.

7 Generation V

Dragon-type Gym Leader

Released on the Nintendo DS, Generation V's Pokémon Black and White are recognized for their metropolis setting, loosely based on New York City. Players were overwhelmed by the design and scale of the region.

Sinnoh is host to a variety of gym leaders, many of which were memorable. Whenever a game has a Dragon-type as its final gym leader, you know you're headed into a tough battle. Depending on what game version you played, you would face Drayden or Iris in the final Gym battle.

6 Generation VI

This is the generation of Pokémon containing Pokémon X and Y. The games start in Santalune City, where players must face Viola, the Bug-type gym leader. Beating her two Pokémon is not as hard as other generations, although facing a gym leader early in the game is seldom easy.

There are examples of tough trainers like Valerie, the Fairy-type gym leader. Valerie has a level 42 Sylveon, an Eevolution introduced in Pokémon X and Y. The most difficult might be Olympia, the Psychic-type gym leader. She is the seventh trainer, wielding powerful Pokémon like Sigilypg, Slowking, and Meowstic.

5 Generation VII

Pokémon Sun and Moon headlined Generation VII of the main series Pokémon games. This generation was an outlier because it didn't contain traditional Gym battles. Instead, players have to defeat Trial Captains and Totem Pokémon. Only by defeating all seven Trial Captains and eight Totem Pokémon can you get the Z-Crystal of the trial. A game without Gym battles could've been disastrous, but Pokémon Sun and Moon winded up pulling it off.

4 Generation II

Generation II of the mainline Pokémon games contained Pokémon Gold, Silver, and Crystal. These games didn't have incredibly hard puzzles, but the battles were quite intense. At the end of the game, you face Trainer Red, the Pokémon Champion, but not before meeting the Johto gym leaders.

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Whitney is the one that gives players the most trouble. As the Goldenrod gym leader, Whitney's Miltank is resistant to attacks. It's a high-level Pokémon in a low-level area, and it doesn't help that Whitney keeps healing Miltank throughout the battle. The generation's gym battles also include Claire, who is actually Lance's cousin. It's worth noting that Generation II contains gym leaders from the Kanto region. With sixteen gym leaders to face, Generation II might have the best gym leader variety.

3 Generation III

For the first time in the Pokémon series, two-on-two battles were a part of the Gyms. It would've made sense to include this feature in Generation I since the Fighting Dojo in Saffron City contains two gym leaders, but at least we got it in Generation III. The games have memorable gym leaders who gave badges like the Feather Badge, Dynamo Badge, and Balance Badge. The unique Pokémon set Pokémon Ruby, Sapphire, and Emerald up for exciting Gym Battles.

2 Generation VIII

Pokémon Sword and Shield are the most dissimilar to the other main series games. Eight generations later, we find reasons to return, with one reason being the games' memorable gym leaders. By studying whats super effective and not very effective against element types, one can breeze through this generation.

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The game starts with a Grass-type, Water-Type, then Fire-type. Three powerful elements right off the bat. Players who aren't familiar with the Fairy-type will have trouble beating Opal. Also, with Dynamaxing thrown into the equation, these battles heat up quickly.

1 Generation I

As the generation that started it all, Generation I contains the most memorable gym leader battles. From the get-go, players are fascinated by gym leaders like Brock and Misty. The gym leaders' ties to the animated series provided a backstory for each leader.

Each character has a dynamic personality that fits their corresponding Element-type. Lt. Surge has a candid electric personality, while the Psychic-type Sabrina is a little weird. We also can't forget the Cinnabar Island Gym Leader Blaine. His Pokémon quizzes were unlike anything seen in the series. To become a true Pokémon Master, you had to prove it in more ways than one. Pokémon Red, Blue, and Yellow could be the best generation overall, including its gym battles.

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