While (still) on their way to Nimbasa City, Ash and co. decide to take a break. Ash teaches Oshawott to keep its eyes open underwater so it can use Aqua Jet properly. Later, Scraggy encounters some Foongus. The Foongus use PoisonPowder and all the Pokémon except Oshawott get poisoned. The only known cure are herbs grown at the bottom of a pond and it was up to Oshawott to save the day. But what can it do against a Palpitoad and a Stunfisk?
This is the second episode where Oshawott proves himself. The first was BW031.
This is the second time Ash looked up Palpitoad on the Pokedex since the last episode.