As the description says, look for cannibal ghouls. (They don't currently show the quest details in their tooltip.)
And it's not enough to kill a cannibal ghoul... you need to talk to the resultant spirit to get credit.
Quest
Defenders of Darrowshire
A World of Warcraft quest in Eastern Plaguelands. Facts and objectives from the current retail game data.
The highest voted Wowhead comments for this page. They are community notes, not TheWoWDB comments.
If you can afford to invest in Elixir of Detect Undead unless of course you're a hunter. The Ghouls do not have their names highlighted so it can be a tad difficult finding them through the vastness of plaguewood.
It makes life easier.
FYI All alchemists can make this with a skill level of 230 and requires only one Arthas' Tears.
I found most of the cannibal ghouls in and around Terrordale, the west most point in the blue area.
Quest facts
The client quest POI data records no map location for this quest, so no map is shown.
Check whether you have already completed this quest
in-game: /run print(C_QuestLog.IsQuestFlaggedCompleted(27529))
Description
The battle of Darrowshire was one of the many tragedies that we humans suffered at the hands of the Scourge. Its effects are still felt even today. Many of the town's valiant defenders now roam again as the ghastly servants of the Scourge. We will end their misery. Hunt cannibal ghouls here within the Plaguewood. Many of these fiends were once the good folk of Darrowshire, and destroying their forms now will set their souls free.
Community notes from Wowhead · 12 comments
Top 3 shown aboveThe comments below were written by Wowhead users. They are community notes, not TheWoWDB comments. See them in context on Wowhead.
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Reward details
Reputation: Argent Crusade +250
Led by Tirion Fordring, the Argent Crusade combines the reformed Order of the Silver Hand with the Argent Dawn in one final push against the forces of the Lich King.
Reputation group: Wrath of the Lich King.
Other quests in Eastern Plaguelands that reward Argent Crusade reputation: Rough Roads (+350), Zaeldarr the Outcast (+250), Frederick's Fish Fancy (+250), To Kill With Purpose (+250), Dark Garb (+250), Catalysm (+250).
Item facts are the current retail client’s (ItemSparse); the specialisations for a pick-one item are the ones the Blizzard quest API lists; faction and currency text is the client’s own. Lowest listed price = the US commodity auction house now.
Where this quest fits
After this quest
Taken from a quest that requires this one.
- The Corpsebeasts
To the south, gutless cultists are focused on a grim task: re-animating enormous hunks of flesh, to create giants known as corpsebeasts. Luckily for us, these giants are still lifeless and weak. Take this charm - using it will place a font of holy energy on the ground.
Steps, storylines and map placement from the client’s QuestLine, prerequisite and QuestPOI data; neighbouring quest text is Blizzard’s own (quest API), shortened to its opening sentences.