cianwood city.
the sexth gym leader jasmine is in the lighthouse
the 15th gym leader in soul sliver is blaine and he uses only fire type pokemon
in the cities
you have to get all 16 gym badges
in his gym
the 16th gym leader is:Trainer Blue
The fifth Gym Leader in Pokemon LeafGreen is Koga, the leader of Fuschia City's Gym. He specializes in Poison-type Pokemon and hands out the Soul Badge.
He is on Cinnabarr Island.
go to the Pokemon gym
Blue, the last gym leader in kanto region
The fourth gym leader in Pokemon Soul Silver is in Ecruteak City.
The Gym and Gym leader is in the bottom left of the city near the Pokemon center.