Grimer is a formless sludge Pokémon born from polluted waterways and seabeds exposed to lunar radiation. It has two bulging eyes with beady pupils, a wide-open mouth, and a gray tongue, but no visible legs—just two stubby arms with three fingers each. Its purple body is basically a walking bacterial colony; the germs are so concentrated that anywhere Grimer settles becomes completely barren. It's constantly leaking bacteria-laden fluid from every part of itself, and if it ever runs out of internal germs, it dies. Pieces break off as it moves around, each one becoming a new Grimer, and when two Grimer merge, they create entirely new toxic compounds.
Being totally formless gives Grimer a huge advantage: it can squeeze through basically any crack or crevice. It uses this to slime its way into sewage pipes and feed on wastewater, which is pretty much its entire diet. Its population depends entirely on how much waste is available, so you'll find them in polluted waters, urban areas, and factories. Unfortunately, environmental cleanup efforts have cut off their food supply, and Grimer populations are now facing extinction.
Forms
Grimer has a regional variant called Alolan Grimer. When the species was introduced to Alola to manage the region's growing garbage problem, it adapted to eating solid trash instead of liquid sludge—which completely changed its body composition. Alolan Grimer is green with a yellow sludge stripe running along its lower lip and around the back of its head, a bright blue tongue, and small black crescent marks behind its eyes. It's also got two blunt "teeth" on its upper jaw that are actually crystallized toxins formed from its diet. These crystals are dangerous to touch, and when they fall out, lethal poison leaks everywhere. The upside: unlike regular Grimer, Alolan Grimer doesn't reek.
Around one hundred Alolan Grimer live near Alola's waste sites, actively helping with garbage disposal. The species has become so effective that it's now widely used in waste facilities worldwide. Alolan Grimer is always hungry and has to constantly eat—trash, manufactured products, whatever. Its arrival in Alola actually crashed local Garbodor populations since Alolan Grimer preys on them. You can also find them in Blueberry Academy's Terarium Coastal Biome.
Evolution
Grimer evolves into Muk.
Alolan Grimer evolves into Alolan Muk.
Content compiled by AnimeList.moe from publicly available sources.
