The planet Wuria came into conflict with Earth Gaia for a long time. 

The abundance of resources was too tempting to be beyond the reach of Wurian Emperor Song Dark.

After many years of wars and struggles, a compromise was found to maintain a lasting peace.

In exchange for technological contributions, the inhabitants of Gaia agreed to cede their resources to them.

The Wurians were an aggressive race in general and devoid of feelings like the Gaians could be. Which made them particularly unusual for the Wurians, unable to feel so many feelings. 

There was a caste on Wuria known as the Warriors of Wu who attempted to stop the Emperor in his attack on Gaia. They were a kind of resistance against the tyranny of their Emperor Song Dark. Their mystical order was aimed at protecting the Wu, a mythical animal that appeared to restore balance to the world. 

From generation to generation this order transmitted the prophecy to its knight members.

But they were pursued in order to be eradicated because they opposed the conquest and invasion of many planets. Their word began to spread among the population, which was not to the taste of the emperor.

They were finally largely decimated despite their art of Wubo No Koï, secret and mystical art of the Warriors of Wu. Faced with the armies of Song Dark they were outnumbered and had to escape.

Some managed to escape and no one heard from them for centuries.

Guardians of a prophecy announcing the coming of a deliverer bringing love, justice, and truth back to the universe, they were now on the run. 

They contented themselves with passing on their art and prophecy while waiting for the day when this world would need them again.