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| Ash's Muk
サトシのベトベトン Satoshi's Betbeton
Ash's Muk (Japanese: サトシのベトベトン Satoshi's Betbeton) was the ninth Pokémon that Ash caught in the Kanto region, and his tenth overall.
In the anime
In Sparks Fly for Magnemite, Ash and his friends were traveling through Gringey City, which was in the midst of a power failure. The local power plant was being overrun by the mysterious Poison-type Pokémon Grimer. After the swarm was located, the Grimer's leader, a Muk, came and challenged the group. However, the vast numbers of Magnemite and Magneton in the city combined attacks to clear out the Grimer, leaving only Muk. With the aid of Pikachu and a Magnemite that was following it due to an electrical build up, Ash defeated and captured the Muk. It was then immediately sent to Professor Oak's Laboratory because its stench was so rancid that it could seep through the Poké Ball. However, Muk's horrid smell seemed to have disappeared by its later appearances as neither Ash, nor anyone around him, was affected by it.
Muk reappeared in Showdown at the Po-ké Corral when Ash, Misty, Brock, and Gary visited Professor Oak's Laboratory.
Muk easily absorbing attacks
Muk's first battle was in The Fourth Round Rumble, where it was selected for use in the Indigo Plateau Conference. After Jeanette Fisher's high-level Bellsprout had trounced Bulbasaur and Pikachu, Muk made a surprise appearance as Ash's third Pokémon. Muk easily absorbed Bellsprout's physical moves and Razor Leaf and then simply smothered it with Body Slam, winning the match for Ash.
In The Mystery Menace, Ash used Muk to help him and Tracey find Misty, Togepi, and Bulbasaur, who was kidnapped by a giant Bulbasaur in the sewers of Trovitopolis. Muk and Kingler also offered to fight for Ash in the Orange Island Championship battle against Drake in Hello, Pummelo!, but Ash chose Tauros instead.
Muk asking Ash to let it fight
Muk was reunited with Ash when he returned home in A Tent Situation. Muk insisted on fighting Team Rocket, and Ash ordered it into battle instead of choosing Bulbasaur. Muk managed to resist Razor Leaf attacks and a Poison Powder from James's Victreebel. Lickitung's Lick was even less effective, wiping Muk's face ineffectively to the point of causing pleasure instead of damage. It was then put to sleep by Sleep Powder, but awoke after Gary intervened and drove Team Rocket away.
Muk battling Gary's Scizor
In A Farfetch'd Tale, Muk crowded into Ash's screen with Kingler, Tauros, and Snorlax to wish him luck for his next Gym battle with Whitney.
Muk's only other major battle was when Ash called it up from Oak's Lab in Can't Beat the Heat!, along with Tauros, Snorlax, and Heracross in order to fight Gary in the Silver Conference. It was sent out originally to fight Blastoise, and the two fought to a stalemate, with Muk's Sludge Bomb deflected by Rapid Spin and Blastoise's physical attacks absorbed into Muk's body. Ash pulled Muk for his Bayleef quickly after. It was sent out to fight Scizor later, who dodged a Sludge Bomb easily. Muk absorbed both Quick Attack and Metal Claw, but Scizor was able to throw Muk using the latter attack, ultimately defeating it with Swift.
In Showdown at the Oak Corral, Muk was seen crushing Cassidy, Butch, and all of the stolen Poké Balls. It was also seen crushing Tracey when he opened the door to Oak's Lab for Delia.
In The Right Place and the Right Mime, Muk welcomed Professor Birch to Pallet Town with its usual friendliness.
In An Old Family Blend!, Muk appeared at Professor Oak's lab. It was then transferred to Ash for a brief reunion. However, Muk was not seen participating in the Lily of the Valley Conference.
In New Places... Familiar Faces! and Farewell, Unova! Setting Sail for New Adventures!, Muk smothered Professor Oak while Ash called him from Professor Juniper's laboratory.
Muk was reunited with Ash in The Dream Continues!, where it and the rest of Ash's Pokémon posed for a group photo with him.
In Alola, Kanto!, Muk was sent out of its Poké Ball so it could be compared with its Alolan Form. It immediately smothered Ash upon seeing him.
In Show Me the Metal!, Muk joined Professor Oak in observing the data about Meltan that Rotom sent to him.
Personality and characteristics
Muk showing affection for its Trainer
Ash's Muk is an extremely happy and affectionate Pokémon. It is particularly affectionate towards Professor Oak and as a recurring gag first seen in Who Gets To Keep Togepi?, it would always smother the Professor whenever Ash would make a call to the lab.
Muk loves humans and it's not too particular what kind.
Muk's affection also extends to its Trainer, second in enthusiasm only to Bayleef, despite only having fought for him on three occasions. Muk obligingly crushes Ash in excitement whenever Ash returns to the lab or summons it to his party. Its affection also extends to complete strangers, as was seen when it completely ignored Jessie's Lickitung in order to hug Jessie, also smothering James's Victreebel in excitement. It also smothered Professor Birch upon meeting him in The Right Place and the Right Mime. Professor Oak suggests that Muk's overwhelming displays of affection is simply because it loves humans.
Muk differs from most of Ash's other Pokémon in that it is a defensive Pokémon, with a low attack power and a small moveset. It has never been shown to be damaged by a physical attack, with its opponents' moves always absorbed by its sludge body. Despite being quite powerful and good in battle, it has only ever defeated one opponent: Jeanette Fisher's Bellsprout.
| Using Body Slam
| A † shows that the move was used recently, unless all moves fit this case or there are fewer than five known moves.
In the manga
Muk in The Electric Tale of Pikachu
In the Ash & Pikachu manga
Muk only appeared on the scoreboard in One Half Of A Poké Ball.
In The Electric Tale of Pikachu manga
Ash caught Muk off-screen and later used it as his last Pokémon is his battle against Jeanette in Welcome to the Big Leagues. Jeanette's Bellsprout had no chances of using its techniques against Muk's slimy body, and Ash won the battle.
- Pokémon the Series: XY is the only completed series in which Muk has not appeared.
- Out of all the Pokémon that Ash has obtained in their evolved forms, Muk is the one he has owned the longest.
- In Pokémon Yellow, a game highly based on the anime, Muk can be found while walking in the Power Plant, making a direct reference to Ash's Muk, which was also found in a power plant.
For more information on this Pokémon's species, see Muk.