Note: There are other series with the same name: Underworld, Underworld (Greg Cox), Underworld (Toombs)
- Series: Underworld (Apollos Thorne) Series Record # 54798
- Series Tags: LitRPG (3)
- Underworld (Apollos Thorne)
- 1 Level Up or Die (2017) by Apollos Thorne
- 2 Through the Belly of the Beast (2018) by Apollos Thorne
- 3 Sanctuary (2019) by Apollos Thorne