Gastly was Captain's Pokémon he used in the Orange League 300 years ago. Using Gastly and Haunter, the captain managed to win the trophy and store it in his ship. The ship sank and Haunter and Gastly remained in their Poké Balls. Due to an underwater expedition, people managed to retrieve the trophy, but Gastly and Haunter were awakened. When Team Rocket came to the ghost ship, Gastly and Haunter took the trophy and protected it, then told Ash, Misty and Tracey the story via Meowth. When Team Rocket woke up, they were blasted off, while Gastly and Haunter used their powers to levitate the ship away.