After you settle the dispute between groudon and/or kyorge. After you take care of them, the gym "Wallis" is in should be open. It's close to the top middle of sootopolis city. He is an ice/water gym leader
go catch Giratina and then go to the Sunshore City gym and fight the gym leader
go to hearthome city and fight the gym leader there
Go Right To Snowpoint City Then Fight The Gym Leader :D Go Right To Snowpoint City Then Fight The Gym Leader :D Go Right To Snowpoint City Then Fight The Gym Leader :D
You go to the Hearthrome gym
You have to go to Veilstone City and go to the gym. Then you battle gym trainers and go past them. You will get to Maylene, the third gym leader. You can battle her. Unless you're talking about the Hearthome Gym. Fantina is the leader of that gym. If that's what you meant, you need to fight the Veilstone Gym and the Pastoria Gym first.
you go to blackthorn city to fight the 8th gym leader
You go inside the gym, and there is usually a maze you have to get through to be able to fight the gym leader. After that, you just walk up to the leader.
You have to go in the lighthouse and get the gym leader. Then you fight the gym leader and the guy in front of the town will leave and you will be able to get there.
you go to sunnyshore city but don't go to the gym go to the lighthouse and you will find the gym leader talk to him and then he will go back to the gym so you can fight him
you go to the 7th gym leader (in the seafoam islands) and after yu beat him you go back to cinnabar island and blue will say you are ready to fight him p.s. the 7th gym leader is fire type
The 16th gym leader is Blue. You can only fight him after you win all 15 gym badges. after you get all 15, go to cinnabar island, blue will be there. show him your badges and he will return to the gym so you can fight him
I think you have to go back to Hearthome city. There you can enter the gym and fight Fantina.