Battlegear of Wrath

Battlegear of Wrath is the tier 2 warrior set.

Source
Tier 2 drops mainly in Blackwing Lair. The legplates drop from Ragnaros in the Molten Core.

Trivia

 * In Heroes of the Storm, Sonya, a character from Diablo, has a skin called "Wrath Sonya" (which also makes her weapons look like Quel'Serrar and Ashkandi, Greatsword of the Brotherhood.