All of these set pieces drop off bosses in Molten Core. Tier 1 is an armor set containing eight pieces of epic quality gear.
#WOW LEGION PTR SHADOW PRIEST PVP UPGRADE#
Tier 0.5, also known as Dungeon Set 2 pieces are all acquired through completing quests that upgrade your current Tier 0/Dungeon Set 1. Vestments of the Virtuous (Priest Tier 0.5)
The Tier 0 Set or Dungeon Set 1 for Priests is called Vestments of the Devout.