Crown of the Corrupted Conqueror

Helm of the Corrupted Conqueror is a tier 13 armor token. It can be exchanged at in Stormwind City or  in Orgrimmar for the following items:

Source
On normal and heroic mode, this item drops from Warmaster Blackhorn 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.