Once upon a time, somewhere in the dawn of Azeroth's history, before the Sundering split the world in two, there was a race of warlords called the mogu. Violent and cruel, the mogu fought relentlessly against everything -- including each other. That is, until one day when one mogu sought out the history and secrets of his people's past, discovering that they were creatures of far more potential, far more purpose than any had realized. It was a secret long forgotten, and the mighty Lei Shen not only uncovered it, but brought that secret back to his people.
For untold years after Lei Shen emerged from the depths of the Isle of Thunder, the mogu reigned supreme on Pandaria. They captured and enslaved the weaker races, forcing them into servitude. It was not until after the death of Lei Shen that the pandaren race finally rose up with the hozen, the jinyu, and even the grummles to disrupt and reduce the armies of the mogu to rubble, taking the continent of Pandaria back as their own and ruling in peace.
In the waning hours of Lei Shen's inevitable downfall at the hands of Azeroth's heroes, we'll soon be leaving these relics of ages past behind, and instead focusing on the future of our world. But the history of the mogu, the history of Lei Shen is not a tale we should soon forget.