What is covered in Gym Leader Strategies (Johto) for Pokemon HeartGold and SoulSilver?

Each Johto Gym Leader presents a unique challenge. Falkner (Flying) is weak to Rock/Electric. Bugsy (Bug) is weak to Fire/Flying/Rock.

How do you complete Gym Leader Strategies (Johto) in Pokemon HeartGold and SoulSilver?

Each Johto Gym Leader presents a unique challenge. Falkner (Flying) is weak to Rock/Electric. Bugsy (Bug) is weak to Fire/Flying/Rock.