Jade-Skull Breastplate

Source
This item drops from Nethermancer Sepethrea in The Mechanar wing of the Tempest Keep.

Graphic matches
and combine graphically with  in a single suit of armor. They drop from Dalliah the Doomsayer in The Arcatraz wing of Tempest Keep and Warchief Kargath Bladefist in The Shattered Halls of Hellfire Citadel respectively.