Cavernous Maximus

Almost as far down as the magma caves, there lies a room entirely shrouded in mist. The fog here is so thick that the cave seems infinite on all sides. If you look closely, you can see the...
WHOA! WHAT IS THAT?! The natives here couldn't have missed that.
Where ARE these natives anyhow? How do they survive in caves of lava and giant flying monsters?
What Is this place....
Rendered in Photoshop.