Basculin (Japanese: バスラオBasslao) is a Water-type Pokémon introduced in Generation V and is set to appear in Pokémon Black and White. Its classification is the Violent Pokémon. It has two forms which are dependent on the version. It is basically another Magikarp except Basculin can learn TMs and Basculin doesn't evolve.
Basculin is a fish-like Pokémon. In its red form, two parts of its body are separated by a bright red-orange stripe and has spiky white fins. Its blue form, however, will replace the red-orange stripe with a blue one, and its fins and eyes have a sleeker design.
Its name is probably a combination of Bass and Masculin.
Basculin was first shown within footage from the Pokémon Searcher BW tour on August 7, 2010. It was used by Cheren in the demo. It was officially revealed on the October issue of Coro Coro on September 11, 2010.
Basculin's Red Stripe Forme is exclusive to Pokémon Black while its Blue Stripe Forme is exclusive to Pokémon White. Its forms do not change, it's the first Pokémon to do this.
Though with the use of the Super Rod or surf on a Rare Pokémon spot will always yield the opposite form.
While most Pokémon can have up to 3 abilities legitimately (two primary abilities and a hidden ability), Basculin can legitimately have four, as an NPC in Driftveil City in Pokémon White trades away a Blue-Striped Basculin with the ability Rock Head.