Demoniac's Threads

Demoniac's Threads (aka Demoniac Jewels) is the Zandalar Tribe set for warlocks.

Source
Most Items of Demoniac's Threads can be acquired through quests given by Al'tabim the All-Seeing, who can be found on the Yojamba Isle in Stranglethorn Vale.

The quests require a given Reputation with the Zandalar Tribe and a token from a boss in Zul'Gurub.

The only exception is, which is formed by combining a with Gri'lek's Blood, Renataki's Tooth, Wushoolay's Mane, and Hazza'rah's Dream Thread. While the voodoo dolls can be found in Jinxed Hoodoo Piles (which are found throughout Zul'Gurub), the rest can be found on the respective boss in the Edge of Madness, in Zul'Gurub.

RPG
"It is said that the witchcraft used to empower these ghoulish accessories is similar to the dark magic employed by the Atal’ai priests of the fractured Gurubashi empire. Only the most accomplished troll priests are capable of crafting these macabre artifacts without falling under the sway of the malevolent powers they must wield to do so."