Fighting is Meaningless

Blade was the son of Ying's family. The duke, his father, was the head of the military power of the Empire, and it was pretty easy to see a desire for more growing.
The Emperor and the Crown Prince, fearing Ying's family would commit treason with all that power they were gaining, decided to give the order to end their legacy, and that's how soon Blade found himself with his whole family dead, bleeding, on the floor of his manor.
Blade, in his last breath, prayed for a chance to get his revenge on the Empire, and on the Crown Prince. He did desire to give them a painful death, enjoy, savor every drop of blood coming from their bodies and actually carry out the plan to conquer the Empire.
His soul full of madness, hatred and bloodthirst, somehow goes back in time of one year before his family's death sentence.
Knowing all the military expeditions and events, Blade slowly plans his revenge and his first goal is to get closer to the Empire's territory.
It's when he gets appointed as personal guard to the Crown Prince himself, that he slowly understands how dark and impure the Royal Family is.