Hazza'rah's Charm of Destruction

Hazza'rah's Charm of Destruction is a warlock-specific trinket which increases your spell critical chance for a short period of time. It increases the critical strike rating of your spells by 140, and is extremely useful in PvP. The trinket is a part of the set called Demoniac's Threads.

Source
To create this trinket you need the.

This item can be acquired through crafting or another combine-type effect.

RPG
"This broach is carved from humanoid bone to look like many small skulls in tight concentric circles."