There are currently 7 sets of Elite Four members and 1 Champion, corresponding to the number of Generations that the main series games have been through (although Kanto and Johto share their respective Elite Four location, the Indigo Plateau, which, technically, is in the Kanto region).
The Elite Four is a Trainer Class and title given to four Trainers that qualify as being the best Trainers in their respective regions, with only the Pokémon Champion above their skill level. Artwork of the Kanto Elite Four in Pokémon: Let's Go, Pikachu! and Let's Go, Eevee!.
