The Ata'mal Terrace, formerly known as the K'arani Terrace, is the northern of two sections of the Black Temple that lie outside its massive gates. It is filled with fel orcs and drakonid in service to Illidan Stormrage. It's also the location of the ata'mal crystal shard known as the Heart of Fury, which is required as part of the Black Temple attunement quest chain.
The area was holy to the draenei, but the fel orcs dug up special ore from that place and created corrupted weapons and armor with it. These armaments were retrieved, cleansed and reforged with naga ore by the Shattered Sun Offensive.