Black Plague (Hib)
DISCLAIMER: Your Steps and Tasks may be different
I did not capture the spam text, or even the journal entries before a certain point. (Approximate) journal entries are noted by #. Items are noted by[Item]. Otherwise it's my comments or notes.
Start the quest by going to the healer Waljan. Waljan is concerned about a plague affecting people in TNN.
1. Waljan directs you to go to Eavann, in Tir na Nog. Eavann is located downstairs in the building opposite the entrance to the Nightshade / Ranger guild.
2. Eavann directs you to speak to Tiarnan, in Tir na Nog. He has been ill.
Tiarnan is located upstairs in the same building as Eavann. Talk to Tiarnan and he gives you a [Sealed Letter for Keriann] for his sister Keriann.
>From this point on, journal entries are verbatim.
3. Take Tiarnan's letter to Keriann, in Howth. Keriann is located inside the Chief's hut. Give her the letter and get some quest spam.
4. Continue speaking to Keriann, in Howth, about her brother.
Keep talking to her and eventually she gives you back a [Note to Tiarnan]. She asks if you would like some cash for your troubles. I replied "No", and received 13,836,044 experience (a level 41 druid). I have no idea what the cash reward would be. (if you say "Yes" for some cash for your troubles you receive 2 gold)
5. Return Keriann's Note to Tiarnan, in Tir na Nog. Take the horse back north, and run back into TNN to see Tiarnan. Give him the note.
6. Continue speaking with Tiarnan, in Tir na Nog.He likes chatting with you, and rewarded me with 6,918,022 experience. He directs you to Eavann.
7. Talk with Eavann to see if she has heard any more news from the Druids. Eavann chats for a bit, then directs you back to Waljan.
8. Return to Waljan, in Tir na Nog, and speak to him about Tiarnan's health.Run back over to Waljan, and speak to him.
9. Speak to Waljan to see if you are sick with the disease. To no one's surprise, you are sick so Waljan wants you to fetch an item that he can use to make a cure.
10. Travel to the Coruscating Mines and slay a Glow Worm. Bring the worm fungus back to Waljan for a cure.
Glow Worms are located just inside the entrance to CM. The [Worm Fungus] pops into your inventory like any other quest or one-time drop, but is marked as being stackable. It is capitalized like a post-20 kill task item.
11. Take the worm fungus back to Waljan in Tir na Nog. Run and take a horse back to Waljan. Hand the item to him, he mixes up the cure and you are healed.
12. Speak with Waljan to see if he has found out anything new. He has, of course, and send you out to kill the source (?) of the plague.
13. Journey to Darkness Falls and slay Archivist Borath. Return to Waljan, in Tir na Nog, with the Stoppered Wondrous Potion.
Archivist Borath can apparently be single-pulled if he is up, through the other mobs in his area. After killing him, you get two items, a [Stoppered Wondrous Potion] and an Unstoppered Wondrous Potion].
14. Return to Waljan, in Tir na Nog, with the Stoppered Wondrous Potion. You may keep the Unstoppered Wondrous Potion for yourself.
Run back to TNN, give the [Stoppered Wondrous Potion] to Waljan. The experience reward was 13,836,044 points. Waljan mentions coming back to talk to him again in case he has other work for you.
The Unstoppered Wondrous Potion is a 1 charge, 65% heal potion with a level 37 requirement.
I am told that this might be the prerequisite for a latter quest that requires killing Legion.