• English / United States: Ash's Noibat
• Japanese / Japan: サトシのオンバット
• Japanese (Romanized) / Japan: Satoshi no Onbat
• Japanese (TL) / Japan: Satoshi's Onbat

While training in a forest near Hyakkoku City, Ash's Hawlucha found an egg which he brought to Ash Ketchum. He decided to go back to where it was found to see if there was a nest but by the time he got there, the egg started to hatch. Ash's Fletchinder was instrumental in helping the egg hatch as it has an Ability called "Flame Body" that makes eggs hatch faster. Ash Ketchum and his friends didn't know what kind of Pokémon egg it was until Noibat hatched.

Noibat cries by using the move Supersonic which is quite deafening and it won't stop until Ash Ketchum pets it as it thinks he's its parent. Its favorite food is fruit and it can tell the ripeness of a fruit.

Ash's Hawlucha and Ash's Fletchinder helped it learn to fly by teaching it first how to glide on the wind. After an encounter with Rocket Gang in which Ash's Hawlucha protected Noibat it returned to Ash Ketchum and he asked Noibat if it wanted to travel with him and it agreed.

Ash's Noivern is the evolved form of Ash's Noibat. It evovled during a battle against Zapdos in which Ash's Hawlucha was hit and was falling out of the sky. Ash's Noibat quickly went after Ash's Hawlucha and on its way there, it evolved and managed to rescue it. As a result of evolving, it also learned the move Boomburst which was instrumental in the battle against Zapdos and defeating Team Rocket's mecha which was trying to capture Zapdos. Once Zapdos realized that Ash's Noivern wasn't actually trying to hurt it or capture it when it protected it against Team Rocket, it was thankful and discontinued its aggression towards Ash Ketchum.