The game's collection data lists Robe of Midnight Down as sold by a vendor NPC in Warspear.
Vendor
Zone
Map
Waypoint
Other items it sells
NPC #93909
Warspear
-
-
170
Vendor NPC, zone and position come from the client's collection source tables (CollectableSourceInfo and CollectableSourceVendorSparse); coordinates are the in-game map readout.
Build history
First seen in build 5.5.4.69585 (Mists of Pandaria).
Read from the World of Warcraft client build files.
How Robe of Midnight Down Compares
Who It Suits
Cloth is the armor type Mage, Priest and Warlock wear. With Intellect, Robe of Midnight Down suits Discipline, Holy and Shadow Priest; Arcane, Fire and Frost Mage; Affliction, Demonology and Destruction Warlock.
Similar Items
The 10 items nearest to Robe of Midnight Down (item level 40) in item level among Armor > Cloth, Chest slot, from item level 35 to 39.
4 other items in the current build are also called Robe of Midnight Down. Same-name entries are usually a different rank, faction, quest stage or reward track of the same object.
Blizzard numbers items as they are created, so the named items next to ID 96091 (96086 to 96096) were usually added in the same batch as Robe of Midnight Down: the same quest line, zone, vendor or reward set.