Pikachu was one of several different Pokémon designs conceived by Game Freaks character development team. Artist Atsuko Nishida is credited as the main person behind Pikachus design, which was later finalized by artist Ken Sugimori.
Who created Ash Pikachu?
This Pokémon spent less than 1 episode as Pichu. Ashs Pikachu (Japanese: サトシのピカチュウ Satoshis Pikachu) is the signature Pokémon of the Pokémon anime, and the first Pokémon that Ash obtained on his journey as a Pokémon Trainer, given to him by Professor Oak. Pikachu usually travels outside his Poké Ball.