|Min Coin: 2g, 99s, 47c|
Max Coin: 3g, 12s, 97c
a gem of terror
The quest asks you to find the caves in Dread Basin in Feerrott. This is behind the Temple of Cazic-Thule, past the lake surrounded by phantasms, Amygdalan warriors and glare lords. The cave is at -1937, -15, 515 . Walk into the cave and past the first group and you'll update the first part of the quest.
The 2nd part says to "hunt the beasts that congregate within the cave" to find the answers. It took about 3 kills to get a gem of terror, which leads me to believe it's a random update. Click on the gem once you get it and the quest is completed.
Note: The gem is not a chest or body drop. It was an auto-update and you just receive it.