There are 18 types in the Pokémon franchise, but some are more common than others, especially when talking about Gyms and their specializations.

Fans know only a few details about Pokémon Scarlet and Violet, but they can at least expect a return to the franchise's classic elements after the detour that was Pokémon Legends: Arceus. For example, the new games will most likely feature the return of the Gym system.

The Gym challenge is the backbone of most main series Pokémon games. Some are easy, others are extra challenging, and they all showcase a particular Pokémon type. However, some types seem to be a favorite of Game Freak because they constantly show up in Gyms across the main series. It might've taken eight generations for a Dark-type Gym, but Grass is a constant in nearly every game.

Bug might be the worst type in Pokémon. Notoriously frail and offensively weak, Bug-types are super effective against three types and have three weaknesses. However, they are also resisted by seven different types, making them less than ideal in battle.

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Three different gyms have Bug-type specialists. In Johto, Bugsy serves as the leader of Azalea's town Gym. Over in Unova, Burgh is Castelia Gym's resident Bug-type specialist, while Viola fulfills the same role in Kalos' Santalune Gym. The Bug-type isn't the best, meaning most leaders would want to avoid it.

Once the most overpowered type in the franchise, Dragon is now severely nerfed due to its weakness to the new sheriff in town, Fairy. Still, Dragon remains resistant to four types while only being resisted by Steel. Some of the most powerful non-legendary Pokémon are Dragon, so it's not like the type is in the gutter.

Most Dragon specialists are Elite Four Members or Champions, but three are Gym Leaders: Clair from Johto's Blackthorn Gym, Drayden and Iris from Unova's Opelucid Gym, and most recently Raihan from Hammerlocke Stadium in Galar.

The Normal type has a bad reputation, somewhat unwarrented. It isn't a good type per se, but it's far from terrible. Instead, it's as its name implies. Normal is only weak to Fighting and isn't super effective against anything. Furthermore, it resists nothing, dealing basic damage to most other types.

Normal has three Gym Leaders across the games. Whitney, the head of Goldenrod Gym in Johto, is one of the toughest Leaders in Pokémon, almost single-handedly elevating the type. Norman from Hoenn's Petalburg Gym is also an incredibly skilled trainer, further helping the Normal-type's reputation. The other two Leaders, both from Unova, are Lenora and Cheren, but none is particularly noteworthy.

The Fire-type is great offensively. It is super effective against five types, including the otherwise overpowered Steel, while resisting a whopping six. Logically, it is weak to Water, but its weakness to the extremely common Rock-type can be potentially problematic.

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Fire has a balance between Gym Leaders and Elite Four members, leaving it as the star of four Gyms. Blaine from the Seafoam Islands in Kanto, Flannery from Lavardige Town in Hoenn, Chilli from Striaton City in Unova, and Kabu from Motostoke City in Galar are the fiery representatives of the type.

Ice is also in contention for the worst type in the franchise, mainly because of how ridiculously frail it is. Some Ice moves are quite powerful, and the type is super effective against the mighty dragons, but it is otherwise unimpressive. Ice has four weaknesses, and four types resist it, making it rather unbalanced.

Surprisingly, many Gym Leaders favor Ice. The type boasts five specialists across the generations, starting with Johto's Pryce, leader of Mahogany Gym. Candice from Snowpoint Gym in Sinnoh, Brycen from Icirrus Gym in Unova, Wulfric from Snowbelle Gym in Kalos, and Melony from Circhester Gym in Galar would follow suit.

The fearsome Fighting-type is super effective against an impressive five types. However, it is resisted by the same amount while only resisting three types. Its three weaknesses mean that it is quite balanced, but Trainers should be cautious when using it.

Five Gym Leaders specialize in the Fighting-type. Chuck from Johto's Cianwood Gym was the first one, followed by Brawly from Dewford Gym in Hoenn, Maylene from Veilstone Gym in Sinnoh, Korrina from Shalour Gym in Kalos, and Bea from Stow-on-Side Stadium in Galar.

Electric might be the best type in the franchise. It has strong stats, only one weakness, and three resistances. Electric is super effective against two types, including the overwhelmingly common Water, and is only resisted by three types, one of which is itself. Some of the best single-type Pokémon are Electric, further improving the type's standing.

Logically, Electric would be a favorite of several Gym Leaders. Lieutenant Surge from Vermilion City in Kanto, Wattson from Mauville City in Hoenn, Volkner from Sunishore City in Sinnoh, Elesa from Nimbasa City in Unova, and Clemont from Lumiose City in Kalos are the Electric Gym Leaders, bringing the type's number to five.

The poor Rock-type became worse and worse with every new generation. It has five weaknesses and is resisted by three types, although it is super effective against four types while resisting the same amount. Overall, it isn't as bad as some might think, but it's certainly not great.

Still, five Gym Leaders opt to use it, often using the best Rock-type Pokémon in their teams. Brock is one of the anime's most beloved characters and the franchise's first Rock specialists. Roxanne from Rustburo's Gym in Hoenn, Roark from Oreburgh's Gym in Sinnoh, Grant from Cyllage Gym in Kalos, and Gordie from CirchesterGym in Galar followed his example.

Grass is a beloved and very common type, found in the early routes as easily as on the Victory Road. However, it is somewhat weak. It has five weaknesses and is resisted by a whopping seven types. Furthermore, it is only super effective against three types, although it does resist four types, even if one of those is itself.

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Five Gym Leaders specialize in the Grass Type, cementing its popularity. Erika from Celadon Gym in Kanto was the first one, but two generations passed before the second one came in the form of Eterna Gym's Gardenia. Cilan from Striaton Gym, Ramos from Coumarine Gym, and Milo from Turnfield Stadium followed.

One of the first Starter types, Water is one of the best in the franchise. It only has two weaknesses and resists four types while being super effective against three. Three types resist Water, but it is overall a very well-balanced option, especially for new Trainers.

Water is the most common type in the franchise, so it makes sense it would have the most Gyms. Misty, one of the most famous Gym Leaders in Pokémon, was the first one. Following her were Wallace and Juan from Sootopolis Gym in Hoenn; Crasher Wake from Pastoria Gym in Sinnoh; Cress from Striaton Gym and Marlon from Humilau Gym, both in Unova; and, most recently, Nessa from Hulbury Stadium in Galar.

NEXT: 10 Best Gym Leaders In Pokémon, According To Ranker

David is a twenty-eight-year-old Mexican writer and reader. Having studied Marketing in school, he spent three years working a nine-to-five desk job before deciding to pursue a writing career. He now works as a Senior Writer in ScreenRant and does some more freelancing job, talking about the entertainment business he so loves. Currently, he's also writing his second novel while actively working to get his first one published.