Players have been selecting a companion in every Pokémon region since the Kanto, and typically that choice is comprised of three starter options; a Water-type, a Grass-type, and a Fire-type. However, a certain electric mouse that many know as the main mascot for the Pokémon series can also be a choice for players, despite only appearing as a starter a few times collectively. Because of this, some fans may wonder why Pikachu's appearance as a starter in the original Yellow version didn't add a permanent electric type to the line-up, and if it is actually a true starter Pokémon.
Pokémon Yellow was released for the Game Boy Color in September of 1998, a little more than a year after the air date of the first episode of the animated series, Pokémon: Indigo League, during April of 1997. As many Pokémon fans know, the animated series introduced Ash and his beloved best friend and Pokémon companion, Pikachu. When Ash shows up late to Professor Oak's lab, all the normal starter Pokémon have already been taken, and all he has left for Ash is a very angry, reluctant Pikachu, who Ash determinedly takes to start his Pokémon journey.
Because of Pikachu's appearance in the animated series, Pokémon Yellow commemorated Ash's Pikachu by adding it as a starter for the third game in the original Kanto region trio. However, as the series moved forward, releasing Silver and Gold in the Johto region, players again saw only three starter Pokémon. This set of three would remain the traditional set up for the next seven generations. Pikachu wouldn't make another appearance as a starter Pokémon until the release of Lets Go, Pikachu! in 2018.
Pokémon's Pikachu Is Technically A Starter, Even If It Only Happened Twice
While Pikachu's past as a starter Pokémon was limited to two official times during the Pokémon game series, and only once in the animated series, technically Pikachu is still a starter Pokémon. Pikachu is often included in special promotion runs of starter Pokémon cards, like the 25th Anniversary Pokémon McDonald's promotion that issued special starter card packs in children's happy meals. Players have the ability to choose Pikachu as their traveling companion for a region, which is the only qualification in the series to mark a Pokémon as a starter, and this makes Pikachu the odd forth starter option in Kanto.
Because of Pikachu's status as a starter Pokémon however, some players may wonder why an Electric-type fourth starter wasn't included from Yellow forward after it was included in the original Kanto games. It isn't clear why developers decided to make Pikachu and its Electric-type a one-time option for players, though it likely had to do with Pokémon Yellow being a promotion for the animated series. Either way, while Pikachu's history as a starter may seem more complicated than Squirtle's or Charmander's, it is by definition, a starting choice for Pokémon players and may potentially be seen as a starter again in future Pokémon titles.