Physiology
Muk look very similar to its previous form, Grimer. The main differences are that Muk is larger than Grimer, and has a wider mouth and smaller eyes. It is also usually shown with its left arm being much larger than the right one, along with a strand connecting its upper and lower lip when its mouth is open. The sludge it is made of is apparently less dense than water as it has been shown to float on it in the anime.
Gender differences
None.
Special abilities
The toxicity of Muk's form has reached the point where a single drop of it can make an entire lake stagnant and rancid. Its footprints are toxic enough for a person to contract influenza if they are touched. Their infamous stench increases in the summertime, due to the toxic substances in its body intensifying. Their ability to exist in the environment without it becoming completely hazardous to other lifeforms may be attributed to their ability to actively control their toxins, as they would likely never want to deliberately pollute a river or spread any harmful diseases.
As a fully evolved Pokémon, Muk is capable of using the moves Hyper Beam and Giga Impact.
Behavior
In the wild, Muk usually take charge of their family of Grimer and are very protective.
Habitat
This Pokémon likes warm and moist places. Groups of them accumulate in dirty places, such as garbage dumps or sewers. They sometimes also reside in dirty back alleys of towns. Despite their penchant for thriving in dirty, contaminated places, they do seem to have a limit as to how much pollution they can tolerate, as no Muk lived in the Lake Lucid of fifty years ago until some work was made on purifying it. Wild Muk are normally found only in Kanto.
Diet
- Main article: Pokémon food
Muk will eat anything that is already contaminated.
- Although Muk's body is very poisonous, it doesn't seem to harm Ash and the others when Muk is 'hugging' them. This is probably because it is able to control whether it gives off poison or not similar to how Ponyta can choose whether or not to burn the person that touches it. Croagunk is another Pokémon which is able to control the amount of poison it uses via its fingertips when using Poison Jab, or Sharpedo activating its ability, Rough Skin.
- Muk is tied with Mew for the shortest English name out of all Pokémon.
- Muk's height is given as 3'11" but it is seen to have altering heights as it can expand and become taller or spread out and become shorter.
- Haunter and Muk are the only two Pokémon whose weight does not change as a result of evolution.
- Even though Muk's Red, Blue, and LeafGreen Pokédex entries state that its footprints are poisonous, Muk does not have a footprint in the Pokédex, or even feet.
- In Pokémon Platinum, Muk is one of the few Pokémon not in the Sinnoh Pokédex, and not introduced in Generation IV, to have a new sprite. Meowth, Oddish, Hitmonlee, Ninetales, Primeape, Krabby, and Registeel are the others.
- All of Muk's backsprites depict its left arm in the air.
- Muk's backsprite is different in FireRed and LeafGreen than from Ruby, Sapphire, and Emerald. Muk is shown to have part of its face seen along with its hand.
- Muk's evolutionary family, along with Gulpin's, Koffing's, and Trubbish's families are the only Pokémon to learn Sludge by leveling up.
- Coincidentally, they are all pure Template:Type2 Pokémon introduced in odd numbered generations.
Origin
It appears to be a pile of living sludge. Muk may also be based on the imagined fear that heavy pollution, caused by the leakage and/or improper disposal of toxic/radioactive waste, may result in the creation of new and undesirable life.
Name origin
Muk is a corruption of muck (generally something filthy).
Betbeton may be derived from べとべと betobeto (sticky).