Starting as a Son-in-law to Establish an immortal Family - Chapter 1979 - 655:

In his previous life, Lin Mu was the top assassin on Earth. He accidentally traversed to the Eternal Immortal Realm, where, over the span of eight hundred years, he cultivated from an ordinary mortal to the realm of an Immortal Emperor.However, as he was undergoing the tribulation to become an Immortal Emperor, his enemies ambushed him and his Divine Soul drifted through the cosmic Chaos for several hundred years. Now he possesses a body which belongs to another man also named Lin Mu, a live-in son-in-law of the Qin Family in River City who was constantly mocked and humiliated.“Rest assured,” Lin Mu mutters. “Since I have taken your body, I will naturally avenge you.”

In Ten Heavens Domain, full of respected powerhouses, juvenile Ling Tian accidentally obtained a mysterious iron sword. He refined the Supreme Martial Dao, studied the Divine Spirit Array Laws, fought Ten Thousand proud and arrogant Heavenly Clans, and was undefeated! Seven Feet Sword Tip sweeps away the world, within the Ten Heavens, I am the Supreme God Monarch!

- Description from Novelupdates

When a person dies, they either die light as a feather (aka unimportant) or heavy as Mt. Tai (aka very important).

In the vast forests, towering mountains, and the wide seas, mythical creatures spread across the wide world. Some are large and terrifying, while others are small and gentle; half of them enjoy harming humans, while others wish to help them.No one knows exactly when they appeared. Some say they existed before the human race emerged, while others claim they appeared alongside the first humans in this world.Their forms and abilities vary, and different races deal with them differently. Some despise them and consider them monsters, while others revere them. Yet everyone agrees on one thing: it is best not to attempt to meddle with them.Everyone, that is, except for one person.