The dungeon is the newest area to explore in RivWorld. Each dungeon is randomly generated and contains 2-4 monsters, as well as a final boss.
There are 5 different enemies found in the dungeon.
Skeletons drop bones.
Vampires drop garlic.
Ghosts drop token bags.
Zombies drop earthworms.
Mummies drop rubies.
Each dungeon contains a hidden key, which is required to enter the boss room. Although keys are randomly generated, they are always found by clicking a slightly out of place wall decoration.
There is currently only one boss, but more are likely going to be added in the future.
Tetra is similar to other enemies, until it reaches half health, in which it will submerge into the acid. When Tetra is submerged, you cannot reach it to deal damage. Recycling items will cleanse the acid, making Tetra take 3 damage per item recycled. Note that this only works while Tetra is submerged.
Upon defeating Tetra, you can receive consumable fish, as well as a legendary pet, Tetro. Tetro has a 1/1000 chance of being found when collecting from the recycling bag, making it the rarest pet in RivWorld.
Treasure chests are also located around the dungeon, and contain various resources, similar to the forest chests.