Description
The miners here don't seem to only be digging for sourcestone. The Endless Court took so much out of the Deepstrike Mines, it's unlikely they could need too much more... They must be looking for the relic in the story. The question is: are they digging everywhere as blindly as they seem? Or do they have a more specific goal?
While we explore down here, why don't you scale the cliffside and search among the Endless for whatever clues you can find to their purpose?
Upon completion
You say the tamer was demonstrating the gnar eating away at stone for Alsbeth?
Gnars are rock eaters. Of course. If Alsbeth wanted to extract a great amount of rock faster than her slaves could ever manage, gnars would help. But she'd still need a lot of them. Where are they all? How are they getting so many of them under their control?