Gastrodon

Ground

Due to Storm Drain and its solid mixed bulk, Gastrodon provides a vital Water immunity for Ground teams, allowing it to wall troublesome Pokemon like Barraskewda, Rotom-W, and Keldeo. This is very beneficial for its teammates, as Gastrodon can prevent Water-type moves from being spammed and force the opponent to play around it. Its access to Recover also gives it a huge edge over Seismitoad, since it can consistently wall the aforementioned threats without being too affected by chip damage. A neutrality to Ice allows Gastrodon to repeatedly take hits from threats to Ground teams such as Weavile, Galarian Darmanitan, and Mamoswine as well. Storm Drain's Special Attack boost can also help make Gastrodon less passive, allowing it to fire off powerful Scalds. However, replacing Seismitoad means that Gastrodon can be taken advantage of by a huge threat in Azumarill, which is able to OHKO it with Knock Off after a Belly Drum boost, proceeding to possibly sweep the rest of the entire team. Gastrodon is typically passive and can be almost completely useless against foes like Substitute Hydreigon, Substitute Kyurem, Tapu Bulu, and Zarude. Despite having solid mixed bulk, Gastrodon can be exploited by many powerful wallbreakers such as Tapu Lele, Rillaboom, and Crawdaunt due to Knock Off.