We Agreed to Be a Righteous Martial Artist, but Why Are You Covered in Magic Light?

Traveling through the Yong Dynasty, Cheng Yu found that demons and ghosts were everywhere here. But he is just a helpless poor man living at the bottom of the dynasty. Monsters eat people! In this situation where he could die at any time, Thanks to the timely awakening of the system, if you kill the enemy, you can harvest the remaining soul of the opponent after death and turn it into spiritual essence, which can be used to deduce martial arts! In order to protect himself, Cheng Yu was forced to embark on a path of killing God. So—— Kill the tiger demon, obtain three hundred spiritual treasures, and successfully deduce the "Devil-Slaying and Demon-Slaying Sword"! Slay the tyrannical military commander, gain 20,000 souls, and complete the performance of "Walking on Snow and Dragon Steps"! Kill the Immortal Lord Beimian, obtain hundreds of millions of souls, and successfully deduce the "Beidou Immortal Killing Sutra"! … The more enemies you kill, the more demonic, evil, and evil energy you accumulate in your body. Thousands of years later, stepping on a mountain of corpses and a sea of ​​blood, with countless resentful souls wailing at their feet, Cheng Yu, the only martial immortal in the world, strode forward. There was blood rolling behind him, and murderous intent filled the sky. While hundreds of millions of creatures bowed their heads, they couldn't help but mutter: No, our Martial Immortal... Why is he covered in magic light? Shh! Stop talking nonsense, what kind of magic light? That's black-red fairy light!