After obtaining all eight Kanto Gym Badges and making it through Victory Road, you will arrive to Indigo Plateau where the Pokemon League is found. The Pokemon League is comprised of the Elite Four and Kanto Region Champion, five trainers you must defeat consecutively in order to become the next Champion. These trainers are the best of the best found within the Kanto Region, so be prepared for five difficult Pokemon Battles in a row.
The third Elite Four Member is none other than Agatha, the same who specializes in using Ghost Type Pokemon. Ghost Type Pokemon are usually weak against Dark Type Attacks and Ghost Type Attacks; however, they aren't really the best Pokemon to have when facing Agatha. This is because all five of her Pokemon are each part Poison Types, giving them a huge weakness against Psychic Type Attacks. With this in mind, it would actually be best to have at least one Psychic Type on your Pokemon Team (as well as a few Pokemon with a Psychic Type Attack) in order to defeat Agatha.
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