The Ruler Of Darkness - Chapter 2Book 3:

Three years into Qin Yu's marriage, his wife and in-laws all hated him.

A young boy named Chen Zong got lucky and found a mysterious Sword Seal. With the help of it, he rose to be a God in Sword who defeated innumerable top talents in all universes from a remote borderland.

- Description from Novelupdates

Inside the 3000m underwater station, an international group of scientists and engineers live and research for possible settlement of entire human race. Park Mu-hyun, a reserved dentist joins the station in hopes for a quaint life in the deep sea. However, things quickly go south when the station gets attacked by a mysterious group of people.As the water starts to fill in the living quarters, Park Mu-hyun grabs his backpack and immediately runs for his life, but where to? Now, the peaceful station becomes the ultimate survival stage of cult madness and chaos.