Ashachu

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Ashachu is the name given to Ash, by fans, when he was transformed into a Pikachu by the magician Lily, at the end of the episode Hocus Pokémon. Ash remained in this form until the beginning of the next episode As Clear as Crystal, where he was reverted back into a human by Lily.

Though this was a very minor occurrence in the Anime series, it has become a target among some fans, being used in fan-fiction or fan art.