You delicately top off the empty bottle; a sample of the foul substance that churns under the platform of the cauldron now oozes back and forth inside the fragile glass container.
Once we successfully analyze the sample drawn from the Writhing Haunt's cauldron, it will provide us with a third avenue to deliver a devastating counter agent against the Scourge!
Completion
Another finely executed mission, <name>! This makes three cauldrons available to us to turn against the Scourge. If Kel'Thuzad's necromantic dominance over these lands wasn't as strong as it currently is, I'd dare say you'd shut them down completely!
Apothecary Dithers will have a report on what this cauldron - as well as the other cauldrons subverted - will require to deliver our counter agent to the plague. With that, the time has come to bring the last cauldron of the west under our influence!
Patch 1.6.0 (12-Jul-2005): Shadow Priestess Vandis at the Bulwark should now properly buff players who complete any step of the "Return to the Bulwark" quest in Western Plaguelands.