Pokémon Definitive Platinum: 4 badges — Cobble (Maylene, Veilstone City)

What opens up at this point in the game, and everything you can catch by now that you couldn't before.

Newly reachable

Newly catchable (25)

CarnivineCarvanhaCastformCleffaCroagunkEeveeExeggcuteGloomGrimerHappinyJigglypuffKangaskhanKoffingMagbyManaphyParasectPichuQuagsireSharpedoSkorupiSquirtleSunfloraSwalotTropiusWynaut