Name: Zhun (pronounced Zhun)
Mask: Telekinesis (but he doesn't know how to use it)
Assigned region: none
Early on, Zhun went missing. No one could figure out what happened to him until he started killing powerful beings who had gone corrupt. He was a hidden assassin, and no one ever saw him save for his victims. When Makuta Teridax took over the Brotherhood, he assigned Gorast and Icarax the task of finding Zhun. They were unsuccessful. Teridax dispatched other agents in an effort to find Zhun, and even hired the Dark Hunters Tracker and Eliminator, before the Makuta Dark Hunter War ended any BoM-DH cooperation.
When Artahka ordered that anyone who knew the location of his island be killed, the OoMN agreed to carry out the task, but many of their targets died before the OoMN got to them, killed by Zhun. How he even knew of the Order's mission is a mystery.
When Makuta took control of the MU, he finally tracked down Zhun, placing him under an illusion of fighting the last surviving Makuta and using Zhun's essence to make Rahkshi. Finally, when Makuta was fighting Mata Nui, Zhun broke free of this illusion, and Teridax killed him.
Zhun had a hood that obscured his face, and he only showed his face to those he was about to kill. He wore a Mask of Telekinesis, but he did not know how to use it nor did he care to.
Back view. Yes, those gears help hold his shoulders in place.
And here's a Tahu:
CC appreciated. Bye!
Edit: redid head, torso, added weapons.