Dungeons are randomly generated and named areas or structures containing more difficult enemies and rare loot. Every dungeon has a Boss.
Types of Dungeons
Dungeons can be buildings, which have a linear route to the Boss and usually only one dead end. These dungeons include:
Dungeons may also be above-ground natural features. These include named:
When you are close enough to the dungeon, it shows the name of it on the map and you can see the difficulty from the color of the text (Red/Extreme, Orange/Hard, Blue/Medium and White/Easy).
Be wary of spike traps - spots where tall spikes will periodically stick out of the ground and retract again. They deal varied amounts of damage, be it nearly insignificant damage or the occasional instant death trap, and make a distinctive sound. These are only found in linear dungeons.
Note that enemies will respawn about 10 minutes after you kill them, as well as when a new day comes at 0:00, so being inactive in a dungeon for a long period of time is not recommended.