Paul's Gastrodon is a Pokémon that Paul caught in Sinnoh. It was used in Paul's battle with Ash in the Sinnoh League as his second Pokémon. Gastrodon was able to overpower Ash's Staraptor but Buizel was able to defeat the Sea Slug Pokémon.
Gastrodon was Paul's second Pokémon used against Ash in the Lily of the Valley Quarter-Finals. After a blow from Quick Attack, it used Muddy Water as a counter shield, and crushes Staraptor with Body Slam when it tries to use Aeiral Ace. It the uses Water Pulse straight up, and as it goes back down, that Gatrodon would jump off at the last second, leaving Staraptor no time to dodge. However, Staraptor uses Close Combat to get Gastrodon off, but is recalled once Gastrodon unleashes Ice Beam. Buizel then comes in, and uses Ice Beam for Ice Aqua Jet and finished it with Ice Punch.