Why Pikachu Won't Evolve In Pokémon Yellow

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Players jumping into Pokémon Yellow for the very first time may be left wondering why Game Freak disabled the evolution feature for the game's Starter Pokémon Pikachu. The Pokémon franchise originally made its debut in Japan in 1996, before launching worldwide two years later with the Pokémon Red and Blue RPGs. The classic Generation 1 game received a Pokémon Yellow edition in 1999, which many consider the best version of the Kanto region. Newcomers revisiting Red and Blue's third edition may be left confused, though, as Pikachu is unable to evolve even after a Thunder Stone is used on the adorable yellow Pokémon.

Following the release of Red and Blue, the Nintendo franchise became an absolute cultural phenomenon with the launch of the Pokémon anime in 1998. Children around the world became hooked on the adventures of Ash Ketchum and his sidekick Pikachu. The show was so popular, that Game Freak released Pokémon Yellow in 1999 to make the Red and Blue RPGs closer to the animated series. The third edition RPG swapped out many NPCs in the game for characters in the anime and featured location changes to match Ash Ketchum's journey through the Pokémon League. Pokémon Yellow's Starter Pikachu was the biggest change made to the Gen 1 RPG's storyline, as the Electric mouse was now the player's first Partner Pokémon given to them by Professor Oak.

Related: Every Pokémon Anime Character In Pokémon Yellow

As a result, players are not actually able to choose a Gen 1 Starter at the beginning of Pokémon Yellow, as Pikachu automatically becomes the user's main Pokémon throughout the story. Although the RPG's main rival is able to evolve his Eevee, players eventually discover that the evolution feature has been disabled for Pikachu.