I was just watching Pokemon BW Rival Destinies, and Ash’s Oshawott used "Shell Blade". Is this an error in the show, or is it a real move? If it's real, how does Oshawott learn it?
That's a translation error. "Shell Blade" is the Japanese translation for Razor Shell. To answer your question, Oshawott learns Razor Shell at level 17.
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