Is the world of Pokémon really all about Pokémon? Certainly to an extent it is, but there’s another aspect of each game that’s arguably as important as the pocket monsters themselves. They’re the gates that test your skill at every major turn in a Pokémon game. They’re the focal point of every city and the checkpoints on the way to becoming a true Pokémon master. It’s not just about raising every available critter you like. It’s about building a balanced team that will meet these challenges head-on. Of course, we’re talking about Pokémon gym leaders.

In the world of Pokémon, the gym leaders come from all walks of life. Some are just as over the top as the critters they’ll send at you. Others are no-nonsense, putting the foundation of a difficult-to-beat team ahead of all eccentricities. Regardless of their backgrounds and personalities, each of these fellows harness the intense passion of ensuring every trainer that comes through the doors of their gym is worthy of the difficult journey to each region’s Elite Four.

Maybe they’re on this list because they were just too ridiculous to forget. Maybe they’re here because they brought something to the table that the other trainers didn’t. Or maybe they’re here because their ridiculously difficult challenge was the stuff of nightmares. Either way, these gym leaders are the boss battles that have made 20 years of Pokémon a worthwhile series of journeys. These are the 20 Best Pokémon Gym Leaders.

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