The Deep Ones are beings that are worshipped by the people of Hackdirt. They are believed to live deep in the caverns of Hackdirt, hence the name "Deep Ones." The Hackdirt Brethren live in the caverns to be closer to those they worship. Even though they are mentioned by the people of Hackdirt, the Deep Ones are never seen in-game.
- The Bible of the Deep Ones contains Daedric writing, indicating a connection to them.
- The name "Deep Ones" may be a reference to H.P. Lovecraft, as one of his most famous race, save the Great Old Ones, are the Deep Ones.
- It has also been speculated that the Deep Ones have some connection to the Sloads, considering that the Daedric writing in the Bible of the Deep Ones translates into a text identical to that found in N'Gasta! Kvata! Kvakis!.
- They can be heard in the Hackdirt Caverns as an ominous growl, especially if the player turns the in-game music off. This sound effect is unique to the Hackdirt Caverns.
- The Elder Scrolls IV: Oblivion (mentioned only)