Pikachu wasn’t always intended to be the Pokémon series’ mascot, but once it was bestowed the title, one Pokémon’s prospects were irrevocably ruined: Raichu. When Pikachu’s casting as Ash’s trusty partner in the Pokémon animated series solidified its spot as the face of the franchise, Raichu’s fate was sealed. Despite being a fantastic Pokémon in its own right, Raichu has been extremely neglected across all forms of Pokémon media in favor of its pre-evolution.
The Pokémon anime has massive influence in the franchise overall, taking concepts from the video games and applying them in a way that’s marketable while also telling a unique story. While this can lead to some fun scenarios, it means that, generally, the anime will feature Pokémon that receive new video game gimmicks, such as Gen 8’s Gigantamax Pokémon in Sword and Shield, and that video game gimmicks will most likely be given to Pokémon that are guaranteed to appear in the anime. This, of course, means Pikachu — but not Raichu.
Related: Why Pokémon's Original Mascot Got Replaced
Because Pikachu needs to continue to appear in the Pokémon anime, Ash’s Pikachu doesn’t want to evolve, and Ash is content with Pikachu’s decision. This wouldn’t be too bad if there were other Raichu that appeared who could get some time in the spotlight; but instead, the classic anime storyline opted to portray Raichu as mean and unappealing — an ill-natured Pokémon used by unkind Trainers. This started with Raichu’s first major anime appearance as an arrogant Pokémon used by the rude and then-American Pokémon character Lt. Surge. This continued in the first Pikachu short movie, Pikachu’s Vacation, where a Raichu appears as part of a group of bullies who torment Pikachu and its
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