The 8 gym leaders hints and tips for Pokemon Diamond

The 8 gym leaders

Roark/type rock/weakness fighting and ground type moves

Gardenia/type grass/weakness is fire type moves

Maylene/type fighting/weakness is flying type moves

Crasher Wake/type water/weakness electric and grass type moves

Fantina/type phychic/weakness bug,dark, and ghost type moves

Byron/type steel/weakness ground and fire type moves

Candice/type ice/weakness fire type moves

Volkner/type eletric/weakness ground type moves

We have more cheats and tips for this game here, Pokemon Diamond cheats