Grimer and Muk

Grimer
The Sludge Pokémon
Type: Poison
Official Registration #: 88
Entry: Born from polluted rivers, this pokémon’s body consists entirely of highly toxic sludge. It consequently thrives on pollution, and as such, it flocks to polluted waterways, where it has been known to clog up entire sewer systems in its zeal to consume raw waste. Despite all of this, grimer populations are considered to be the most prevalent in Kanto and Hoenn, home to two of the most aggressive green campaigns in the world, despite the fact that other regions historically had difficulties with pollution, are centers of mining and manufacturing, and are currently so polluted that their environment has given birth to sentient garbage bags.

Muk
The Sludge Pokémon
Type: Poison
Official Registration #: 89
Entry: The evolved form of grimer, by battle experience. Like its preevolved form, a muk’s body also consists entirely of a highly toxic sludge. However, due to its increase in mass, power, and age with evolution, muk is able to cultivate highly powerful strains of bacteria and viruses that infest every inch of its skin. Physical contact with this pokémon can kill plants and smaller or weaker animals on contact … which should speak volumes about the resilience of pokémon researchers and their assistants as a whole, considering the fact that certain muk express affection via alarmingly frequent tackling.