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Pikachu getting completely curbstomped by a Vigoroth that only knew Scratch (right after spending the first half of the episode telling us several times that Ash made it to the final rounds of the Johto league) may be its most pathetic display ever, even worse than its battle with Snivy.
In fact, Vigoroth only knowing Scratch is such a strange choice, even in the rematch it only knows Scratch and Flamethrower.
Vigoroth learns so many moves that they could've justified Pikachu's defeat much better by having Vigoroth get a lucky freeze with Ice Beam