This WoW set features the full Heroes’ Dreamwalker transmog, which is the druid tier 7 (10-man) raid set. Dreamwalker is obtained by looting Wrath of the Lich King bosses and purchasing some set pieces straight from the vendor with gold. Dropped tokens can be traded for set pieces via Dalaran tier vendors.
How to Get Druid Tier 7? By purchasing from Dalaran vendors and slaying Naxxramas bosses.
How Many Set Pieces?  Helmet, Shoulders, Chest, Hands, and Pants
Druid Tier 7 Transmog: [10-Man Drop Locations]
Note: Druids have three different sets with the same exact look. Tier 6 druid armor tokens can be used to purchase any of the set pieces.
Head: Helm of the Lost Vanquisher [Kel’Thuzad] in Naxxramas
Chest: Chestguard of the Lost Vanquisher [Purchase from Vendor] in Dalaran.
Hands: Gloves of the Lost Vanquisher [Purchase from Vendor] in Dalaran.
Legs: Leggings of the Lost Vanquisher [Thaddius – Gluth] in Naxxramas.
Chest/Hand Vendor (Alliance): Arcanist Ivrenne [37,55] in Dalaran.
Chest/Hand Vendor (Horde): Magistrix Lambriesse [65,23] in Dalaran.
Redeem Token Vendor (Both): Valerie Langrom [51,72] in Dalaran.
Set Name: Heroes’ Dreamwalker Battlegear (hover for set bonuses)
Shoulder: Heroes’ Dreamwalker Shoulderpads
Chest: Heroes’ Dreamwalker Raiments
Hands: Heroes’ Dreamwalker Handgrips
Legs: Heroes’ Dreamwalker Legguards
Set Name: Heroes’ Dreamwalker Garb (hover for set bonuses)
Shoulder: Heroes’ Dreamwalker Mantle
Chest: Heroes’ Dreamwalker Vestments
Hands: Heroes’ Dreamwalker Gloves
Legs: Heroes’ Dreamwalker Trousers