Clefairy & Clefable
Nidoqueen & Nidoking
Nidorina & Nidorino
Sandshrew & Sandslash
Pikachu & Raichu
Ekans & Arbok
Rattata & Raticate
Pidgey, Pidgeotto & Pidgeot
Weedle, Kakuna & Beedrill
Caterpie, Metapod & Butterfree
