Legplates of Carnage

Legplates of Carnage are dps plate legs primarily for warriors. These legplates are a PvE upgrade from Titanic Leggings, while also being a PvP upgrade from Marshal's Plate Legguards or Scaled Sand Reaver Leggings.

Source
This item drops from Heigan the Unclean, the second boss of the Plague wing in Naxxramas.