Route 42 — Pokémon HeartGold & SoulSilver
Every wild Pokémon here, by encounter method.
Route 42 lists 14 Pokémon across 18 encounter methods (grass (morning, hoenn sound), grass (morning), grass (morning, sinnoh sound), grass (night, hoenn sound), and more), between level 10 and 40.
Route 42 in other guides
The same area in other ROM hacks on this site. Each one has its own encounter table.
Infinite FusionPokémon AmbrosiaPokémon GS ChroniclesPokémon Heart & SoulPokémon Polished CrystalPokémon SoothingSilverPokémon SoulgoldSacred Gold & Storm Silver
The original game's table for this area:
Opens up at Beat Whitney — Goldenrod City Gym, badge 3. 3 trainers here: