Mixed
Tank
500High
50Slow
CTier

As a Poison-type, Muk fills a straightforward role. Only weak to Ground, Psychic, and Bug. Known as the Sludge Pokémon. Known as the Sludge Pokemon. The stat spread favors raw physical power.

Muk's built to absorb hits, not race for knockouts. Special bulk with HP doing the heavy lifting. And the medium-fast 1M XP curve means it won't take forever to bring up, worth 2 HP and Attack EVs.

Base Stats
500High
HP105
B
Attack105
B
Defense75
C
Sp. Atk65
C
Sp. Def100
B
Speed50
D
Total500
Low <60
Avg 60-89
High 90-149
Top 150+
EV YieldDefeating Muk yields +1 HP, +1 Atk
HP+1Atk+1DefSpASpDSpe
Details
Catch75Challenging•Medium Fast1M XP•1.2m / 3'11"•30kg / 66.1 lbs•175Base XP
Pokedex Entries

Smells so awful, it can cause fainting. Through degeneration, it lost its sense of smell.

Yellow

Muk Weakness

Vulnerable

Ground, Psychic, and Bug-type moves hit Muk for super-effective damage. Muk's special bulk (base 100 Sp.Def) helps absorb special-type weaknesses, though physical moves exploit the lower Defense.

Gen I Type Chart
  • Only 15 types exist — Dark, Steel, and Fairy are absent
  • Ghost has no effect on Psychic (a known bug, fixed in Gen II)
  • Special stat governs both offense and defense — no Sp.Atk / Sp.Def split
4xCriticali
None
2xWeaki
GroundPsychicBug
½xResisti
GrassFightingPoison
¼xResisti
None
0xImmunei
None
STAB (2)i
GrassBug
3Weak
3Resist
0Immune
Scorei-3
SpikesGrounded — up to 25%
Toxic SpikesAbsorbs on switch
Abilities
StenchHas a 10% chance of making target Pokémon flinch with each hit.
Sticky HoldPrevents a held item from being removed by other Pokémon.
Poison TouchHAHas a 30% chance of poisoning target Pokémon upon contact.

You get Muk from Grimer at level 38. This Poison-type hits 500 total stats and can't produce eggs. The evolution from Grimer pushed Muk to 500 total stats. Sp.Def saw the largest single gain at +50.

How to Evolve

2 Forms
Grimer
#088Grimer
38
Level 38
Muk
#089Muk
Stat Comparison 2 Stages
Grimer
Poison
Muk
Poison
HP
80
105+25
ATK
80
105+25
DEF
50
75+25
SP.ATK
40
65+25
SP.DEF
50
100+50
SPE
25
50+25
BST
325C-Tier
500B-Tier+175
ROLE
Trick Room
Tank
TYPE
Physical
Physical
Breeding not available · Introduced in Gen 2

The recommended build leans into Muk's strengths as an attacker. An item provides extra utility, and flexible EVs EVs back that up. An ability rounds out the package.

Best Build

Utility
Ability
Not in Gen 1
Item
Not in Gen 1
Nature
Not in Gen 1

Best Muk Moveset

  • ExplosionCoverage
  • Acid ArmorSTAB
  • SludgeSTAB
  • Body Slam

Recommended Teammates

Snorlax
SnorlaxGood
Exeggutor
ExeggutorGood
Golem
GolemDecent

The level-up pool is slim, so TMs matter here. Muk's Normal and Fire coverage and more all comes from technical machines, built on top of Sludge for same-type damage. Explosion and Fire Blast are the payoff moves.

Level-Up Moves

Lv 1
Disable
—5520Normal
Lv 1
Poison Gas
—5540Poison
Lv 1
Pound
4010035Normal
Lv 30
Poison Gas
—5540Poison
Lv 33
Minimize
——20Normal
Lv 37
Sludge
6510020Poison
Lv 45
Harden
——30Normal
Lv 53
Screech
—8540Normal
Lv 60
Acid Armor
——40Poison

TM Moves

Src
TM34
Bide+1
——10Normal
TM08
Body Slam
8510015Normal
TM32
Double Team
——15Normal
TM47
Explosion
2501005Normal
TM38
Fire Blast
120855Fire
TM15
Hyper Beam
150905Normal
TM21
Mega Drain
4010010Grass
TM31
Mimic
——10Normal
TM20
Rage
2010020Normal
TM44
Rest
——10Psychic
TM36
Self-Destruct
2001005Normal
TM50
Substitute
——10Normal
TM25
Thunder
1107010Electric
TM24
Thunderbolt
9510015Electric
TM06
Toxic
—9010Poison

Egg Moves

Muk doesn't have any Egg moves

Tutor Moves

Muk can't learn any Tutor moves

Muk appears at decent spawn rates across 5 spots in late-game routes. Sort by Best below if you want the highest rate, or Earliest if you want the quickest access point in your playthrough.

Where To Catch Muk in Yellow

Grimer is your first catch on the way to Muk. You'll find walking and trade encounters from Lv. 23-41 across 10 total spots in the chain.

  1. Grimer
    Step 1Catch Grimer
    Pokémon Mansion - 2F
    GrassLv.26-35CommonMidBuilding
    EFFORTLESS
    Pokémon Mansion - 1F
    GrassLv.23-26UncommonMidBuilding
    EASY
    Pokémon Mansion - 3F
    GrassLv.32-38CommonLateBuilding
    EFFORTLESS
    Pokémon Mansion - B1F
    GrassLv.35-38CommonLateBuilding
    EFFORTLESS
    Power Plant
    GrassLv.33-37UncommonLatePower-plant
    EASY
  2. Muk
    Step 2Muk ✓
    Pokémon Mansion - B1F
    GrassLv.41UncommonLateBuilding
    EASY
    Power Plant
    GrassLv.33-37RareLatePower-plant
    CHALLENGING
    Pokémon Mansion - 2F
    GrassLv.35-38RareLateBuilding
    CHALLENGING
    Pokémon Mansion - 3F
    GrassLv.38-41RareLateBuilding
    CHALLENGING
    Cinnabar Island
    In-game tradeLimitedWaterTrade for (give Kangaskhan)
    LEGENDARY
    or evolve from Grimer (Step 1)

  • Muk works as a tank with 500 BST behind it. C-Tier on our list — a situational pick that fills a niche. That 105 base HP does the heavy lifting.

  • Watch for Rhydon (Ground), Alakazam (Psychic), and Pinsir (Bug) when using Muk. They all hit it super-effectively with STAB.

  • Grimer evolves into Muk at level 38. Muk is the final evolution in a 3-stage line starting from Grimer. At 500 BST, it's got solid stats to work with.

  • Muk is a mixed attacker — base 105 Attack and 65 Sp. Atk. Tanky enough to absorb a few hits, too. But the speed tells the real story — base 50 Speed is low. Priority moves or Trick Room are the way to go. Fits the tank role.

  • Muk appears in 19 games, including Yellow, Red & Blue, and Gold & Silver.

Available since Red & Blue, Muk appears in 19 games spanning 9 generations. Beyond its original form, it gained an Alolan form in Generation 7.