Viridian gym i forgot his name the team rocket boss guy.
In Viridian city.
the last gym leader is called Clair. she use dragon type Pokemon and her gym is in blackthorn city. you cant fight her straight away because you need to fight ho-oh first but when you do fight her she use: dragonair:lvl37,dragonair:lvl37,dragonair:lvl37,kingdra:lvl40. when you are fighting her kingdra she uses a hyper potion when its nearly dead so use your weaker Pokemon to weaken it an the use your tough ones after she uses her hyper potion.The 8th gym leader, Claire, is in the Dragon's Den near Blackthorn City ;But since Pokemon Gold, Silver, HeartGold and Soulsilver all span across the Johto and Kanto regions, there are 16 obtainable badges. Which makes Blue, the gym leader of Viridian City the last gym leader of each game.
the gym leader is pkmn trainer Blue.Pokemon are:exeggutor 55,rhydon 58,arcanine 58,gyarados 52,machamp 56 and pigeot 60. the gym maze is romm full of push tiles. for more info. please visit pokemon.marriland.com. and I am NOT, Marriland.
gym leader erika is in celadon city.i have every Pokemon game.she is the third gym leader.celadon city is next to saffron city.she uses grass type Pokemon. her strongest Pokemon is a victreebell lv.56.
It is in Nacrene city and it is also the Pokemon gym but you will have to fight N before entering
Defeat all gym leaders in johto and kanto and beat red, go to their gyms and they will giv u there numbers. you can then fight them in the fighting dojo next to the gym in saffron city.Serebii.net has it under their Heart gold/Soul silver section.
Not enough info: which gym leader?
The final gym is the Viridian City Gym. Blue is the Gym leader.
Janine I think
The eighth gym leader still awaits, as well as the whole of Kanto.
defeat all the other gym leaders
You beat the 6th gym leader.
you have to get all of the other gym badges in kanto and then go to Cinnabarr island and talk to blue. then go to viridian city and go in the Pokemon gym!
you must frist go to seafoam island where blaine is, he is the 15th gym leader, then go to cinnibar island and a character who is behind the Pokemon center will then say that he is the last gym leader, once you have talked to him he will go to viridian city gym, he is the last gym leader. this is for heartgold and soulsilver :) hope this helped.
after you defeat trainer blue, the last gym leader in kanto, talk to prof. oak. he will give it to you
he is Brock. hes in pewter city.
It's right next to the dojo in Saffron City
Blue, the last gym leader in kanto region