This WoW set features the full Slayer’s Armor transmog, which is the rogue tier 6 raid set. Slayer’s Armor is obtained by looting armor tokens from various Burning Crusade bosses. These tokens can be traded for set pieces via Shattrath City tier vendors. Note that, originally the tier 6 rogue set was only a six piece set, but later changed to include non-matching feet, wrist, and belt, as they still match other Sunwell Plateau raid gear. Matching non-set belt and feet are provided next to the sets below.
How to Get Rogue Tier 6? By slaying Hyjal Summit, Black Temple and Sunwell Plateau bosses.
Are There Multiple Tier 6 Transmogs For My Class? No, some classes do have multiple tier 6 sets (depending on their class trees), but every tier set variation features the same exact transmog look. For example, the paladin has a different set for retribution, holy, and protection, but all three sets share the same exact model and color variation. (Hunter, Mage, Rogue, and Warlock feature only one tier 6 set)
How Many Set Pieces?  Helmet, Shoulders, Chest, Bracer, Hands, Belt, Pants, and Feet.
Rogue Tier 6 Transmog: [Drop Locations]
Head: Helm of the Forgotten Vanquisher [Archimonde] in Hyjal Summit.
Chest: Chestguard of the Forgotten Vanquisher [Illidan Stormrage] in Black Temple.
Wrist: Bracers of the Forgotten Vanquisher [Sacrolash – Alythess] in Sunwell Plateau.
Hands: Gloves of the Forgotten Vanquisher [Azgalor] in Hyjal Summit.
Waist: Belt of the Forgotten Vanquisher [Brutallus – Alythess – Sacrolash] in Sunwell Plateau.
Legs: Leggings of the Forgotten Vanquisher [Gathios – Malande – Veras] in Black Temple.
Feet: Boots of the Forgotten Vanquisher [Felmyst – Sacrolash – Alythess] in Sunwell Plateau.
Vendor 1: Theremis [50,28] in Isle of Quel’Danas sells the [Waist, Wrist, Feet] Vendor 2: Tydormu in Hyjal Summit raid instance sells [Head, Shoulders, Chest, Hands, Legs]
Set Name: Slayer’s Armor (hover for set bonuses)
Shoulder: Slayer’s Shoulderpads
Chest: Slayer’s Chestguard
Wrist: Slayer’s Bracers
Hands: Slayer’s Handguards
Waist: Slayer’s Belt [Transmog Alternative: Bloodfang Belt] Legs: Slayer’s Legguards
Feet: Slayer’s Boots [Transmog Alternative: Black Featherlight Boots]