I was catching up on some of the dev streams I've missed and heard Jorb joking about how an ant dungeon might not be the best noob dungeon, because of their damage. So this got me thinking on what would be the next easiest animal to hunt, other than bats, which would be foxes.
The idea of a fox dungeon isn't very extraordinary, but I had an interesting idea as to how a player would find them. I'm thinking that when foxes hunt and kill smaller animals, they should sometimes pick them up and run off with them. A player can chase after them and the fox will eventually stop, then start digging into the ground, unearthing a fox den and allowing the player to go inside.
As for the dungeon itself, it would be a large, dirt tunnel complex with animal bones decorating the walls and floors. Some loot could be things like "fox fang", "fox claw", "gnawed bone" and other things like that. The boss could be a scarred, pale fox called "The Bandit King" or something similar.