Destroy the four mantid siege weapons at Sra'vess in Townlong Steppes.
The mantid don't just attack in swarms. They're smart. They use alchemy, bombs... and what's worst, they've got siege weapons. Those have the potential to be incredibly destructive if they attack with them. We've got reports that they're building up a force of siege weapons to the west at Sra'vess. Go and destroy them.