Only the female can pass these down in Gen 5. For the first half of the game, you’ll be able to find newPokémon in pretty much every new area.
In most wild Pokémon encounters, the Pokémon's Ability will be one of its non-Hidden Abilities (each having an even chance of appearing if the species has two). Abilities - Pokémon Black 2 White 2 - PokéPlayer. Hidden Grottos are areas in black 2 and white 2 that contain pokemon hidden in forest with their dream world abilities. A Pokemon's ability is determined from a maximum of 3 possible abilities. This also makes Dream World abilities significantly easier to obtain. In addition to that, you may find a standard item sitting in the middle or an item hidden for access with the Dowsing Mchn. 45 VW2 ROUTE 14Grass, Normal: Grass, Doubles:-, ABUNDANT SHRINEGrass, Normal: Grass, Doubles:-, Grass, Shaking Spots: Hidden Grottos:-, SEASIDE CAVE, TOP FLOORCave, Normal: Cave, Dust Cloud:-, Special Event:-Crustle Lv.
In addition, the following Pokémon will have their Hidden Ability: The five Darmanitan in the Desert Resort.