Ash sends an unknown Pokémon in his party to Professor Juniper and adds Sewaddle to his team.
This episode reveals that if a Trainer catches a new Pokémon while having a full party, the Poké Ball will seal itself until the Trainer either deposits it or another Pokémon in the party. This contradicts what was shown in Masaki's Lighthouse (1997), where the Poké Ball simply teleported to Professor Oak's Laboratory.
Ash and his friends reach Pinwheel Forest and meet Burgh, the Castelia City Gym Leader.
As of this episode, Ash has already obtained the same amount of Pokémon he obtained during all 192 episodes of Pokémon the Series: Ruby and Sapphire and all 191 episodes of Pokémon the Series: Diamond and Pearl with six Pokémon. This is also the earliest time in a series that Ash switched his team around, with Sewaddle being swapped with Pidove. He will be doing so with different Pokémon regularly in this series from this point on.
Ash catches a Sewaddle.