Niantic recently hosted a special One Piece-inspired event featuring Straw Hat Pikachu for Pokémon GO. The event took place from July 22 to July 29 and marked the debut of this new hat-wearing Pikachu, inspired by the iconic hat worn by Monkey D. Luffy. Fans also had a chance to encounter Shiny Straw Hat Pikachu in the wild. A Straw Hat with a red ribbon avatar item is also available in the in-game Style Shop. However, this hat-wearing Pikachu cannot evolve into Raichu.
Source: Official Pokémon GO blog
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