On Route 7, near a house by the rails, there is a Hidden Grotto. Enter this Hidden Grotto and you might sometimes encounter a special Watchog. It ranges between Levels 30-35. It also has the hidden ability, Analytic. If the Pokémon with this ability moves last in the turn, its move powers up.
Pokémon Black Version 2 (Japanese) – Catching Watchog (Hidden Grotto)
