Right now, the sprite you are viewing comes from Pokémon FireRed and LeafGreen Versions. Weezing can be found in Pokémon Mansion, but only in FireRed. Its pre-evolution, Koffing, is available in the same place in both versions, and can also be found extremely rarely by Surfing in Celadon City.
nothing can stand in your way</big>
there will not be Black and White sequels for ds pokemon gray will be for 3ds