Sketch is a Normal-Type move introduced in Generation II. The user copies the move that the foe last used, permanently learning the move. This new move replaces Sketch in that Pokémon's moveset, and Sketch disappears. Protect and Detect cannot block this move; if the target tries to use those moves to prevent Sketch then that move becomes the move acquired by Sketch.
The signature move of the Painter Pokémon Smeargle, it learns Sketch once every ten levels and starts with Sketch in its moveset.
Pokémon that Learn this Move via Level-Up
Pokémon that Learn this Move via Breeding
The Sketch Glitch
The Sketch Glitch is a glitch that appears in the Generation 2 games Gold, Silver and Crystal. In the event a Pokémon uses Sketch after using Transform to become another Pokémon, that Pokémon will keep the move that was Sketched after the battle, replacing Transform within that moveset. That move can then be passed down via Breeding with a female Pokémon should the Pokémon affected with the Sketch glitch be a male Pokémon or a Ditto.
Transform sometimes gets drawn via Metronome in Generation 2. Should this happen Metronome would be the move that gets replaced in the moveset of the Pokémon affected by The Sketch Glitch.
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