Breastplate of the Wayward Vanquisher

Breastplate of the Wayward Vanquisher is a tier 8 armor token. It can be exchanged in Dalaran for the following items:
 * Conqueror's Terrorblade Breastplate
 * Conqueror's Darkruned Battleplate
 * Conqueror's Darkruned Chestguard
 * Conqueror's Kirin Tor Tunic
 * Conqueror's Nightsong Raiments
 * Conqueror's Nightsong Robe
 * Conqueror's Nightsong Vestments

Source
This item can be found inside the Cache of Winter after defeating Hodir in the 25-man version of Ulduar.

This item is also sold by the following vendors for :
 * in Dalaran
 * in Dalaran