in sunyshore city
The eighth gym leader in Pokemon platinum is the one in sunny shore city.
in sunnyshore
you must beat the eighth gym leader and he will give you the badge.
The eighth gym leader is in Viridian City. It is the team rocket's leader!
The eighth gym leader of Sinnoh, Volkner, returns to battle you again in Platinum after you beat the Elite Four. When you get to battle frontier, you and your rival have a double battle against Volkner and Flint, an Elite Four member.
you have to battle all the trainers and repeat it ..................... Im sure you can do it.
The fifth gym leader in Pokemon platinum is crasher wake but you get the fourth badge.
The 8th gym leader is Drayden he uses Dragon type pokemon
The 8th gym leader is in Viridian City.
Defeat the eighth gym leader.
The water Pokemon gym leader is in Pastoria City.
the 8th leader in platinum uses electric type so i would recommend using ground type Pokemon..............if you don't have ground type Pokemon don't worry he isn't that good