Quoted By:
There will only be three eras of Pokémon as we know it before the franchise receives a complete makeover. This can be confirmed by the Chinese Zodiac.
Era 1
-Red & Blue (dragon)
-Gold & Silver (mouse)
-Ruby & sapphire (chicken)
-Diamond & Pearl (monkey)
Era 2
-Black & White (pig)
-X & Y (dog)
-Sun & Moon (tiger)
-Sword & Shield (rabbit)
Era 3
-Fact & Fiction (ox)
-Yesterday & Tomorrow (sheep)
-Ebb & Flow (horse)
-A & Z (snake)