Cloak of Flames

Cloak of Flames is an epic cloak.

Source
This cloak drops from mobs in Onyxia's Lair, Silithus, Tanaris, and in Molten Core. Your best chance at getting this cloak is to kill Colossus mobs in Silithus (Ashi and Zora).

Background
Known in some circles as a holocaust cloak, this heavy garment ignites the rage of its wearer in punishing flames.

This is a heavy but normal rust-colored cloak until the wearer draws the hood over her head and speaks the command word; its outer surface erupts in flames that damages any creatures who attack her in melee.