It is part of the Community Day event, which begins this month.
As of January 20, a very special Pikachu that knows the Surf movement will begin to appear in Pokémon GO. As reported from Niantic, this event is part of Community Day, which will also be held in the coming months offering other Pokémon with impossible movements for a limited time. To help us get to the friendly rodent, the bait modules will last three hours; and we will also get double the experience during the course of the event.
[b] Pikachu surfero appeared for the first time in Yellow Pokémon, and since then has not stopped receiving cameos in spin-offs, in the television series, the card game, and of course in distribution events for the canonical games of the saga.
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