The only humans seen in this place are Roostre (who is trapped here), Producer Man (who appears as a hologram of himself) and a Skeleton of an unknown person, that has a backpack with some material Roostre needed; which were a flashlight, a Ju Ju Bees, bottled water and face wipe. This world has sources such as fungi such as mushrooms and some fauna inhabits down here such as Spider and Underwater Snakes, with the latter swimming in the waters.
While the environment itself takes place underground and has muck as the main source, this world is full of flora and fungi such as mushrooms growing, and the backgrounds of mucky world are purple, black and red. Black liquid covers the land, after Roostre breaks out some vines. Roostre was trapped in some green vines tied up in a purple and green glowing fungi cave area. A underwater system is also shown with the ground colored in browns. A trap door is shown to escape the world, which has three flames of fire that can spawn, between the trap door.
Role In The Season
Roostre was trapped in this underground world for a while after the events of "Invictus" and tied up to some green vines. One of the mushrooms has a hologram of the Producer Man spawn along with a red pair of scissors.
After singing a song, Roostre grabs the scissors and cuts the vines with it, then black liquid starts coming off the vines with Roostre being covered in it, causing a steam of that said liquid to spread around the area. Roostre travels the area full of black sludge, finding a skeleton with the materials he needed from its backpack. Roostre then finds out that a red door spawns, but he is interrupted by Spider, who sprays its web and cocoons Roostre into it.
Offscreen, Roostre escapes the cocoon and puts on the face-wipe. Roostre then escapes Spider in the mucky world by swimming in the waters, entering the trap door, which then closed, while Spider was unable to escape due to all of the bodies of water. Roostre then exits the muddy swampland via the entrance into a desert and encounters The Kid. This world is never visited again after this, including the world's entrance.