Pokémon S01E13 - Mystery at the Lighthouse

Pokemon: On the way to Vermilion City, Misty and Brock criticize Ash as he has not truly won his two badges and he isn't take the time to try and capture pokemon. Angered at this, he rushes through the forest and winds up on a beach where he finds a Krabby. He catches the Krabby and its pokeball disappears. Worried about it, Misty explains that trainers can only have six pokemon with them at one time. Still wanting to check on it, they head to a nearby lighthouse where the find the pokemon expert Bill trapped in a Kabuto costume. After freeing him, he tells them a little about the history of pokemon, as well as the mysterious pokemon he thinks will show up to his lighthouse one day. All of a sudden they hear a loud noise, and they head outside. A giant shadowed pokemon starts approaching the lighthouse. However, Team Rocket threatens Bill's perfect chance.