Bog Monster

The Bog Monster is an apparently horrific creature that, according to Klump, eats everything in sight. They reside in the Forbidden Forest on Kongo Bongo Island in the Donkey Kong Country cartoon. As they are never seen, the only physical description given is in the lyrics to one of the songs in the episode, in which it's described as a monster having crystal skin, giant claws, dripping fangs, beady red eyes, stinky breath that could knock over a rhino, hair full of maggots, ears dripping something yellow, and arms thicker than a tree. Of course, this is when Donkey Kong saw it and that was Cranky Kong disguised as a Bog Monster, so there's no way of telling if this is an accurate description.

In the Donkey Kong Country episode "Bug A Boogie", it is revealed that Donkey Kong secretly feared the Bog Monster, as, when he was young, Cranky Kong told him that if he ventured into the Forbidden Forest, the Bog Monster would get him; one day, Donkey Kong disobeyed Cranky Kong and decided to go into the Forbidden Forest, only to encounter and subsequently be scared by a Bog Monster. It is later revealed to Donkey Kong by Cranky Kong that he had, in actuality, simply made up the story of the Bog Monster, and that it was him who scared Donkey Kong when he entered the Forbidden Forest, wanting to teach Donkey Kong a lesson in disobeying him.

Oddly, it seems the Bog Monster may have been an actual creature, as, at the end of "Bug A Boogie", Klump and Krusha, while trying to help King K. Rool out of a pit of quicksand he was stuck in, hear a monstrous roar in the Forbidden Forest, seemingly the Bog Monster.

Diddy Kong also has the unique talent of mimicking the roar of one.