Travel to Master Apothecary Faranell · Undercity (48.4, 69.4) (requires at least Level 16). Use the map button to open exact NPC coordinates on the 2D/3D World Map.
STEP 2 · ZONE & OBJECTIVE ROUTE
Quest zone: Undercity, Ruins of Lordaeron (Dungeon quest — enter with a party via the instance portal). Prerequisite: complete "Unending Torment" first.
STEP 3 · TURN-IN & REWARDS
Return to Unfinished Abomination · Undercity (46.2, 63) to turn in the quest.