Dungeons

Dungeons are small areas that are crammed full of enemies that are levelled quite high, they are also home to 2 bosses. Most can be found at the base of the tree in Highsteppe however I know of 2 that are found in separate areas. Dungeons are a great way to obtain loot that would otherwise be impossible to obtain in base game, providing either blue or purple quality weapons and armour. Dungeons can also be upgraded with Shards to drop even better gear. You should be a minimum of level 10 before attempting regular dungeons and 30 to do shards.

Broken Halls
Broken Halls has been regarded as one of the easiest dungeons in the game by quite a few players, It can be found at the base of the tree in Highsteppe. It's main enemies are the stafrushers and their variants, along with both the Minotaur and the Gorgon. It's setting is that of a run down castle built on the side of a mountain, or somewhere as high, as peering out of the balcony reveals a large drop into a dark purple void.

Airship
The airship is a dungeon that takes place on a ship sailing through the skies. It can be found at the base of the tree in Highsteppe. It's main enemies are the Scav variants and the Tear variants, along with the Chaos Purity and the Chaos Hunter. It's settings is that of a wooden ship soaring high above the skies, It is a small map that uses timers to spawn the bosses and enemies in.