DISCLAIMER: Your Steps and Tasks may be different
Below is the begining information for the Artifact Goddess Necklace, if you know more information please send it in.
Venture to Coral Sanctuary, loc=56k 33k Oceanus Hesperos, and speak to the 4 NPC in there (Unah, Inah, Agnah and Nevsa), they will give you a task to find their a long lost family treasure.
If you agree to help them out, one of the family members will travel with you since the item can only be seen when they cast a spell.
SSW from the Coral Sanctuary is a cave (loc=52k,54k Oceanus Hesperos) where this treasure is located, and it is surrounded by Hammerhead and deep chasm sharks.
You need to get the family member inside the cave for them to cast the spell. If the family member gets attacked by the sharks it will panic and head back home.
Once safely inside the cave the family member will cast the spell and the necklace is yours.
Make sure you talk to at least two family members before attempting this quest. If you only have one family member with you, that member will be unwilling to cast the spell.
After you get the family member inside the cave they will begin to cast the spell. Once they have finished a Dark Devilfish will spawn (yellow to 50 relatively easy fight) and snatch the necklace as it comes free of the statue. The family members will run away and you must kill the Devilfish who will then drop the artifact. I did this solo as a 50 inf. As long as you can sneak past the sharks and only aggro one it's doable.
Argen (50 Infiltrator, Lancelot)
Dianna's Letters, 1 of 3 -- drops from Sobekite on Treasure Island and off Khem Kamu in Notos
Dianna's Letters, 2 of 3 -- drops from Sobekite on Treasure Island and in the Skyros Territory loc=12.6k, 33.3k Meso. also drops from Skyros Breaker and Skyros Trapper
Dianna's Letters, 2 of 3 -- drops from a Skyros Waylayer, Meso
Necklace is usable by all stealth classes, tanks and hybrids.
This artifact is "useable by those who move unseen and those who stand in front of the battle"
Dialog from the 3 scrolls combined (submitted by Staghorn):
"My Dianna, I have failed you. I [thought�] I thought I was ready for the trials. I never imagined I would fail! I am a great warrior, my love, from a great people! Where did I fail? What attributes do I lack? I have not seen any, but if I were to name it, Dianna, I would say [that] I have but one weakness, and one strength.
You, Dianna. I failed the trials for love of you, my weakness. I will thrive though, with your love, my strength. I have been banished, and must leave Atlantis, and return to my land. How that weighs on my heart, to be parted from you, without even a final word, a final kiss. Know though, my love for you will carry me on."
"Dianna, I am outraged! The treasures of Atlantis are not to be given on the whim of some romantic infatuation! How could you give the Goddess' Necklace to one who failed the trials, who is not even worthy of Atlantis? You love recklessly and foolishly. He is a mere fancy. You [cannot] love this wretch. I forbid it!
As for this gift of yours to him, that shall be returned to you, and you are forbidden to keep it in your rooms, lest you decide to give it to some other undeserving meddlesome fool. You [cannot] be so careless with the treasures you hold, Dianna, for they are not yours to give to whom you would please.
They belong to Atlantis. You merely are the caretaker of these treasures. No Dianna, child, there is so much you have yet to learn. I did not expect such foolishness from you. You must stay in your rooms until I have resolved this matter."
"Dianna, my love, treachery, such treachery of your father! I have been beset upon by many enemies and foes here! They have stolen the gift you have [entrusted] to me, which I was to return to your neck on our wedding day! Instead, now, I write with my last breath as the seas here begin to swell and rise, of the treachery and lies of your father!
I have the letters you sent me, and I've stolen a letter from the arbiter, and yes, even as I read the letter from your father to you, I knew you were warning me, but I was blind with hope that his anger had truly abated, and that he loved you enough to treat me honestly. Forgive my foolishness Dianna.
I only wanted to win you as a champion of Atlantis, not a failed warrior banished from the Planes and your great kingdom! My love to you Dianna, I cry knowing this letter will never reach your beautiful eyes, and your sorrow will be great when you learn of my death."
(Earns exp: Slaying many types of magical enemies.)
Artifact also levels from RvR and mobs in Shrouded Isles Outdoors, as per patch 1.71.