Unlike the Pewter City Gym and the Cerulean City Gym, the Vermilion City Gym could be the first Pokemon Gym you have a few troubles with. In order to avoid struggling against the strong Electric Type Pokemon all the trainers in this Pokemon Gym will use in battle, make sure to catch a few of the Ground Type Pokemon found in Mt. Moon on your way to Cerulean City. Ground Type Pokemon take no damage whatsoever from Electric Type Attacks, and their Ground Type Attacks are super effective against Electric Type Pokemon. With a few Pokemon like Onix or Geodude, the Vermilion City Gym will be another quick defeat for you.