Travel to Jarsath Wastes and head to ( -850, -121, -607 ) /waypoint -850, -121, -607, use your mask and speak with a wise rhino at ( -681, -128, -622 ) /waypoint -681, -128, -622.
Kill 10 razorfangs and 3 sick rhinos. The razorfangs can be found scattered in the surrounding area, and the sick rhinos are lying down on the ground around the pond.