The Bladefist (level 70)

The Bladefist is a one-hand fist weapon. It is well known as the weapon of Kargath Bladefist, Chieftain of the Shattered Hand Clan and self-proclaimed Warchief of the Fel Horde.

Source
This item drops from Warchief Kargath Bladefist in The Shattered Halls on Heroic Mode.