Leggings of the Corrupted Protector

Leggings of the Corrupted Vanquisher  is a tier 13 armor token. It can be exchanged at in Stormwind City or  in Orgrimmar for the following items:
 * Wyrmstalker's Legguards
 * Spiritwalker's Kilt
 * Spiritwalker's Legguards
 * Spiritwalker's Legwraps
 * Colossal Dragonplate Legguards
 * Colossal Dragonplate Legplates

Source
On normal and heroic mode, this item drops from Yor'sahj the Unsleeping in the Dragon Soul.

On Raid Finder mode, this item drops from Morchok, Warlord Zon'ozz, Yor'sahj the Unsleeping, Hagara the Stormbinder, Ultraxion and Warmaster Blackhorn in Dragon Soul.