Even an underground prison needs entertainment and Kaida Shadowscale, rumored to have once been a Naga warrior princess, provides blood and excitement for a cost. There is even a protected section for the wealthy and powerful from the surface to come down to the Fighting Pit and bet on who will survive. 

Rumors:

• Why not try a round in the Pit if you need food or money? Not every combat is to the death. 
• The Fighting Pit clinic is attending if you can't find healing elsewhere. 
• Someone is selling organs from the Fighting Pit clinic, and not always from the recently demised.
• If you can make it to the VIP tunnels, your collar won't activate, and you can escape. (Nice thought, but not true.) 
• Kaida has an enormous safe filled with gems and gold in her office.