| This article is about a character featured in the Pokémon anime who has not yet debuted in the English language dub.|
As such, their information may contain romanized Japanese names, rather than dub names.
Gasattsu first encountered Ash, Goh, and Chloe when they arrived in the Wild Area, having been sent by the curator of the Pewter Museum of Science to research the Fossil Pokémon of the Galar region. He apologized after his Mudsdale accidentally sent a large rock at them, which nearly hit Chloe and her Eevee.
Gasattsu gave Chloe tools to work with, and she was soon able to find the components of a fossil and put them into a machine. After preparing dinner, the Fossils were restored and turned out to be a Dracovish and Arctozolt, which were caught by Ash and Goh, respectively.
| Mudsdale is Gasattsu's only known Pokémon. It accidentally sent a large rock flying towards Ash, Goh, and Chloe, which was destroyed when Pikachu used Iron Tail on it. Gasattsu quickly apologized for Mudsdale's actions.
Mudsdale's only known move is Double Kick.