Grimer

Grimer appeared in 1996 video game called Pokémon Red & Green. Grimer is a Sludge Pokémon. Most people and Pokémon dislike the industrial waste created by factories, but Grimer happily feasts on the icky slime. To survive, it has to maintain a certain level of germs that are in its body.

Alolan Grimer
Grimer's appearance in the Alola region developed after it was called upon to deal with a persistent garbage problem. Each crystal that are on its body is from dangerous toxins, and those toxins escape if a crystal falls off.

Appearance
The Grimers that are from the Kanto region are colored purple, but the Grimers that are from the Alola region are colored with dark green on its body, yellow for the jawline and blue for the tongue, also it has two crystal that are sticking on the roof of it's mouth acts like teeth.