Route 11: 12 species in 1 game

Road 11: 12 species across 2 versions

X and Y

X and Y: 11 species
Species	Method	Levels	Chance	Game page
Nidoran♀	Encountering 5 pokemon within grass, flowers, or within a cave	11	60%	All places
Nidorina	Walking in tall grass or a cave	21	5%	All places
Nidoran♂	Encountering 5 pokemon within grass, flowers, or within a cave	11	60%	All places
Nidorino	Walking in tall grass or a cave	21	10%	All places
Hariyama	Walking in tall grass or a cave	22 to 23	20%	All places
Starly	Encountering 5 pokemon within grass, flowers, or within a cave	12	5%	All places
Staravia	Walking in tall grass or a cave	22 to 23	20%	All places
Chingling	Walking in tall grass or a cave	21	10%	All places
Stunky	Encountering 5 pokemon within grass, flowers, or within a cave	11	35%	All places
Stunky	Walking in tall grass or a cave	21	10%	All places
Sawk	Walking in tall grass or a cave	22 to 23	20%	All places
Dedenne	Walking in tall grass or a cave	21 to 22	5%	All places