Huntail and Sakurabyss! The Riddle of Evolution! - S8-E3
Character mistake: The Pokédex entry for Huntail says that it is the evolved form of Clamperl, when it should be an evolved form of Clamperl. This also happens with Gorebyss' entry. (00:02:03)
Answer: There are a lot of fan theories around this, but the most common theme is that Pikachu had another trainer before Prof. Oak, who gave him to Ash. Pikachu didn't appreciate being handed over.
Ssiscool ★