In This Troubled World, the System Forces Me to Be a Lunatic

[Protagonist Dian Lao (slightly Dian does not count as Dian)] [Fast-paced, not frustrating] [No heroine or single heroine] In the era of demons and chaos, Zhang Xun traveled through time and became a jailer guarding a prison. He wanted to reopen the prison on the spot, but he awakened to a system that calculated daily results. Others have worked hard to cultivate, but Zhang Xun only needs to use the butcher's knife to obtain various benefits. Killing humans can reward you with special abilities, and killing monsters can reward you with martial arts realm. Relying on the daily settlement of results, Zhang Xun's mental state is deteriorating (thriving). An unknown demon cultivator said: "I took the Seal of Wrong Souls that I had to kill 10,000 people to get. When I first activated it, he asked me... How many people were killed yesterday..." "To be honest, I think he is a bit too extreme..." A certain demon: "When he killed me, he said something like, 'I am killing you to help you escape the suffering of the world. Even though I am killing you, I really love you!'. How can I not know whether living is bitter or not..." The introduction is too weak, let's move on to the main text!