The Undying Mecha Emperor - Chapter 3 Devour

As he woke up, Wei Xuan realized he returned to the day when the apocalypse had just begun. Wei Xuan, who had a second chance at life, immediately decided: not to go to a survivor base, and not to return to human society, instead, there is only one thing he wants to do now. Find the half-zombie Du Hang, and live with him in the city full of zombies, farming and living together until old age. Wei Xuan, who stayed in the zombie city after being reborn, unexpectedly found out that zombies are not as terrible as humans think…

- Description from Novelupdates

500 years ago, Chen Xi was devoured by a crack in the void and was transported into a cultivation world.

A ritual gone wrong gave him the world's deadliest Class—now all he wants is blood.Zeth stole the most powerful ritual magic in the world from a mad cultist. A Class that's fueled by the blood of his enemies and human sacrifice. One that's illegal to use, punishable by gruesome death. And now that he has it, he's faced with a choice: hide away for the rest of his life from those who would hunt him down, or embrace the power, becoming the hunter to get revenge on the murderer that stole his friends' lives.For Zeth, that's no choice at all.His enemies have to die. And he plans to use every drop of blood, eldritch ritual, and demonic summoning he can to kill them.

Chu Xuan transmigrated to a fantasy world and became the young master of a powerful family. He was rebuked for misbehaving just because he sneezed during a banquet. As punishment, he was banished from the ancestral mansion and was relocated to a remote residence.

He did not mind the punishment at all. He just needed a spot that could allow him to be a shut-in. With the system that would allow him to grow stronger by being a shut-in, the longer he stayed indoors, the more powerful he became.

After being a shut-in for a day, he was rewarded with the Indestructible Body Technique.

After being a shut-in for a month, he was rewarded with the Immovable Mountain Technique.

After being a shut-in for a year, he was rewarded with the Yuxu Celestial Scripture and 100 years of cultivation.

After being a shut-in for 10 years, he was rewarded with the Chaotic Indestructible Body and the Bell of Chaos.

…

Chu Xuan declared, “No one can make me leave my home. I like being a shut-in!”