A gym leader is the person you challenge to defeat a gym. Gym leaders generally specialize in one type rather than many. It is suggested you use a type advantage so it is easier.
Gym Leaders[]
Brock -Rockbell City Gym Leader
Pokemon: Onix
Difficulty Level: 1 out of 10
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Falkner -Skyloft Town Gym Leader
Pokemon: Pidgeotto
Difficulty Level: 2 out of 10
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Athrun -Mt. Arcadia Summit Gym Leader
Pokemon: Dewgong
Difficulty Level: 4 out of 10
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Erin -Mineridge Gym Leader
Pokemon: Ludicolo
Difficulty Level: 6 out of 10
David -Woodcove Gym Leader
Pokemon: Gyarados
Difficulty Level: 8 out of 10