• English / United States: Erika's Gloom
• Japanese / Japan: エリカのクサイハナ
• Japanese (Romanized) / Japan: Erika no Kusaihana
• Japanese (Trans) / Japan: Erika's Kusaihana

Erika's Gloom is her main battling Pokémon and one of her closest friends. As a 10 year old girl, Erika got lost and couldn't move when she had an encounter with a Grimer in an alley. A Gloom was walking by at the time and Erika called out to it to assist her. That Gloom understood Erika feelings and saved her from the Grimer. From that point on, Erika and that Gloom became good friends. Erika's Gloom often uses a stinky cloud that is expelled from the top flower part of its body but it is not designated as a standard move. None of Erika's Gloom's attacks are actually known.

Essence of Gloom

Team Rocket heard about a legendary perfume that is made in the Celadon Gym and attempted to steal it. They tricked Ash Ketchum into working with them so they could enter the gym undetected. They ended up destroying the Celadon Gym in a large fire before they stole what they thought was the formula but instead it was Gloom extract which is used as raw material for perfume.

Gym Battle against Pikachu

In the final matchup, Erika's Gloom was sent out to battle Ash's Charmander and Ash's Charmander couldn't stand the horrid smell of Erika's Gloom and was recalled. Pikachu was going to be matched up with it for the final round of the battle but Team Rocket exploded a bomb in the gym and it caught fire. Everyone except Erika's Gloom escaped safely, so Ash Ketchum decided to go in after it as he thought he was partially responsible for the disaster. Erika's Gloom lets out an unpleasant smell whenever it feels its in danger but Ash Ketchum was able to overcome that by making Erika's Gloom feel safe in his care. He picked it up and carried it out of the burning building. As thanks for rescuing her Gloom, Erika gave Ash Ketchum the Rainbow Badge.