Ash's Pidgeotto uses Whirlwind for the first time.
Brock catches a Zubat, and it is revealed that Misty has a Staryu.
First time Team Rocket says their trademark line "We're blasting off again!".
Brock tells his Zubat to use the move Double Team which acts the same as Butterfree's Whirlwind attack. This is a goof. Double Team's effect is to increase the user's ability to dodge attacks.
This is the first time Brock meets Team Rocket, but he acts like he already knows them.
Seymour: The Moon Stone is an awesome boulder. A million years old or even older. Deep in these caves the meteor hides, though no explorer has found the place of the legendary rock from space. We've studied its fragments for many an hour and discovered it increases a Pokémon's power. And that is why the attackers are here. They've come to take the Moon Stone or so I fear.
Meowth: Don't be scared of Meowth!
Seymour: (while the Clefairy use Metronome) It's an attack the Clefairy use called the Metronome. I've never seen the Clefairy use the Metronome before. Who knows what's gonna happen?!
James: What's that unusual sound?
Jessie: His knees are shaking.
Pokémon Debuts: Zubat, Staryu, Clefairy, Clefable, Paras.
Who's That Pokemon: Clefairy
In the Japanese version, Seymour said how the Clefairy acted as though the Moon Stone was a God. In the dubbed version, they just talked about how the Clefairy pray to the Moon Stone.