First, go to the Burned Tower in the Southeast. Then you see Morty and this guy named Eusine (a guy looking for Sucuine). Then you see your Rival and you battle him. Then you climb down a ladder then you see three Legendary Beasts. Then they will scram and now, you can return to the gym now.
there is no 9th gym
You CAN NOT become a Gym Leader in Pokemon HeartGold and SoulSilver or ANY MAIN SERIES POKEMON GAME.
The 4th Gym witch is in Ecruteak City. He uses ghost type Pokemon.
walk in
The gym is in Blackthorn City.The gym leader is Clair.
He has many types.
In Pokémon HeartGold, you can find the 3rd Gym Leader in Goldenrod City.
awww by beating the 7th gym
try beating the gym leader
its in azalea town
Obtain it from a gym leader.
mahogany town