Grimer

Grimer (ベトベター Betbeter) is a -Type Pokémon, and can evolve into Muk starting at level 38.

Biology
This Pokémon was born when sludge in a dirty stream was exposed to the moon's X-rays. It is composed primarily of putrid, hardened sludge and grime. It smells incredibly foul, and can influence the abandonment of entire cities due to its polluting nature--even weeds don't grow where a Grimer has appeared. Grimer thrives in filthy areas, such as factories, garbage dumps, sewers and polluted water systems. It survives and matures by sucking up polluted sludge that is pumped out of factories, adding toxic waste to its already toxic girth.

Special Abilities
Grimer can have the ability Stench or the ability Sticky Hold. Stench decreases the chances of encountering a wild Pokémon when Grimer is the first party Pokémon. Sticky Hold prevents the theft of Grimer's held item. It enters sewers and other areas with great ease due to its rubbery and semi-viscous body; for example, it can enter barred-off areas by slipping between the narrow bars. If you stick your hand in Grimer, it will be very hard to get it out.

Locations
To get one in Red and Blue, it can be found in the Pokémon Mansion.

To get one in Yellow, it can be found in the Pokémon Mansion and the Power Plant.

To get one in Gold, Silver, and Crystal, it can be found on routes 16, 17, 18 and Celadon City.

To get one in Ruby, Sapphire, and Emerald, it can be found on Fiery Path.

To get one in FireRed and LeafGreen, it can be found while fishing in Celadon City and the Pokémon Mansion.

To get one in Colosseum, it has to be traded from either Ruby, Sapphire, Emerald, FireRed, LeafGreen, or XD.

To get one in XD, it has to be snagged from Cipher Peon Faltly in Phenac Stadium.

To get one in Diamond and Pearl, it can be found on Route 212, with the Pokéradar.

To get one in Platinum, it can be found on the southern part of Route 212 with the Pokéradar.

Side Game Locations

 * Pokémon Snap = Cave
 * Pokémon Pinball: Ruby & Sapphire = Cave
 * Pokémon Trozei! = Phobosphere, Endless Level 35, Trozei Battle, Mr. Who's Den
 * Pokémon Mystery Dungeon: Red/Blue Rescue Team = Magma Cavern (15F-21F), Stormy Sea (20F-29F), Silver Trench (20F-29F), Wish Cave (80-85F), Murky Cave (3F-5F), Joyous Tower (80F-85F), Far-off Sea (20F-29F), Marvelous Sea (B20), Fantasy Strait (B20-B29)
 * Pokémon Mystery Dungeon: Explorers of Time/Darkness = Waterfall Cave (B1-B8)
 * Pokémon Ranger = Underground Waterways

Other information
In the Sonic the Hedgehog continuity, Dr. Robotnik has an assistant called Grimer.

Grimer and it's next evolved form, Muk, are both homages to the monster Hedorah of the Japanese Godzilla Series.