Speak to Yeppa at 4263, -1095, 2046 in the Forsaken Othmir Village in Cobalt Scar to begin this quest.
Lower levels and other squishy crafters should be cautious approaching this area; there are many undead othmir and flying snakes around it.
Make a Necromantic Detector.
Scribe the Recipe: Necromantic Detector, which is a level 92 recipe made with Geomancy at a Forge (in Beta this auto-scribed, check your chat window for a message).
There is an Othmir Forge that looks like a camp fire at 4269, -1092, 2033 . You'll need
Use the Necromantic Detector to find a source of the scourge. It is important to use the detector first, or you won't get the updates.
Right-click and use the Detector. It will put directions in your chat window, use it as many times as you need to. You're looking for the giant bone at 4284, -1096, 2048 . Get very close to it and the quest will update.
Use the Necromantic Detector to find another source of the scourge. You're looking for the giant bone arch at 4417, -1092, 2007
Use the Necromantic Detector to find the another source of the scourge. It's the giant bone at 4306, -1086, 1996 .
Use the Necromantic Detector to find another source of the scourge. Another giant bone, at 4264, -1080, 1968
Return to Yeppa.
NOTE: Do not delete the Necromantic Detector, you'll need it later.