in blackthorn city.
The eighth gym leader still awaits, as well as the whole of Kanto.
Blue (The eighth gym leader) is waiting on Cinnabar. He won't battle you unless you've beat the rest of the gym leaders
The eighth gym leader is Claire in Blackthorn City
The eighth gym leader is in Viridian City. It is the team rocket's leader!
The third gym leader is Whitney.
it depends............................WHICH GAME??!!??!!
The final gym is the Viridian City Gym. Blue is the Gym leader.
Gym Leader Blue
Not enough info: which gym leader?
The 8th gym leader is in Viridian City.
His name is Blue, and he is on Cinnabar Island. Show him the other 7 Kanto Badges and he will go to the Viridian City gym. Then, go to Viridian City and battle him at that gym.
You have to beat team rocket