Alright, so according to Simcraft, Destruction's BiS trinket is dropped by Withered J'im, this week's world boss. I killed him at the start of the week and rerolled, but only got a cloak.
Unstable Arcanocrystal drops from him, though, and since world bosses rotate every week... I'm going to have to wait until he rotates back in for another shot at this trinket?
Isn't this kind of a screwy system, or am I misunderstanding something here?