Hampering their escape
I'm sure you've seen those blue and white platforms hovering over the quarry. They're the transportation the mage hunters used to land their forces here, and now they're loading them up with our artifacts and fragments of our statues.
We must stop them before they leave the quarry.
The small creatures digging in the quarry carry explosives. Take them and use them to destroy the three floating platforms. The leader keeps watch from a fourth, grounded platform, but we'll deal with him afterward.