Stars of Chaos: Sha Po Lang, Vol. 1 by Priest Eornheit

The discovery of violet gold, a vital fuel for steam-powered machines, propelled Great Liang into an age of prosperity. But for Chang Geng, a young man raised on the impoverished northern frontier, the concerns of the empire are as distant as the stars above.

When raiders from the north attack Chang Geng’s small village, he discovers that the life he knows is a lie. His mother, his teacher...even his beloved godfather, the man he trusted most in the world, are not who they seem. As enemies of the empire circle ever closer, Chang Geng must travel to the heart of the capital—with his godfather as his guide—to meet his destiny.