Caught by Ash.
Kanto Pokémon League Tournament - Round 4 - Vs Ash Ketchum - Grass Field Despite looking like a weak opponent Jeanette's Bellsprout managed to KO both Ash's Bulbasaur and his Pikachu. Ash turned to Muk who he transferred from Prof. Oak just before the battle.
Due to Muk's slow speed and bigger size it could not avoid Bellsprouts attack but thanks to its slimy and elastic body it was simply able to absorb them and not feel any damage. Bellsprout continued to launch a number of ounches, kicks and throws but still Muk absorbed them all. After repelling a Razor Leaf attack Muk smothered Bellsprout with its body and after a few seconds of struggling Bellsprout was defeated, giving Ash the victory and earned him a place in the final 16.
Please with its victory it gave Ash a hug which forced Ash to the ground. Ash laughed and praised Muk for giving him the victory.