Pikachu is the partner character in Pokémon Yellow: Special Pikachu Edition.
Unlike Pokémon Red and Blue, which let players choose Bulbasaur, Charmander, or Squirtle, Pokémon Yellow begins with Pikachu. The game was designed with the Pokémon anime in mind, so Pikachu follows the player outside its Poké Ball and refuses to evolve using a Thunder Stone.
The player’s rival receives an Eevee, creating a different starting matchup from the original games. Pikachu’s mood can also be checked, and its reactions change according to the player’s actions. These features made the yellow edition feel more closely connected to the animated series.
Pokémon Yellow was released in Japan in 1998 and later internationally. It remained a Game Boy title, although it could display color when played on a Game Boy Color. The game is an enhanced version of the first-generation adventures rather than a completely new generation.