Owari no Chronicle - Volume 4, Afterword

The first great emperor in the world was betrayed by his confidante and perished. Millions of years later, the great emperor’s soul returned and was reborn as Ye Yan, the son-in-law who was kicked out by the Chu family with a letter of divorce, restarting the supreme journey. Open the gate of immortality, kill the Jiuzhongtian, and cast an invincible name again!

- Description from novelbuddy

Ye Yang, the son of the Ye Family in Eight Desolate City, was once regarded as a genius. He could awaken his Dantian at the age of three and reach the third level of Qi Condensation at the age of five. But after a few years, He was seen as a person without talent because his cultivation was still stagnant at the age of 16. One day, He was framed and kept in a coma after he was rescued.

Ye Yang was originally an instructor in a special troop. He was 21 years old and sacrificed his life to protect an unknown broken sword which was found on Everest. When he woke up, he became Ye Yang from the Eight Desolate City, unexpectedly obtained the recognition of the broken sword and learned the mysterious cultivation method “God Slaughtering Technique”. He then embarked on a path of cultivating through slaughter.

When he was reborn, he swore, “I won’t let those who offended me off.” He wanted to reach the peak step by step, and also carried the mission to uncover the secret behind the Nine Heavens Mysterious Sword.

- Description from Novelupdates

Being sucked into a fantasy world that nobody leaves doesn't sound half bad to Cain. He was a high school dropout with a drinking problem, living off disability due to his poor health, so it's not like he had much to lose except a few faithful friends he didn't talk to enough.

After a long night of drinking, Cain wakes up looking at what he believes to be the character creation screen of one of his beloved virtual reality games, but with no recollection of having purchased it. His unwitting choice to use the Random Character Creation option, unaware that the choice would be irreversible, sends him into this new world as a Puppet Master, a Summoning based class nobody else in the starting zone has ever heard of.

But as he soon realizes, this is no game, him and hundreds of others have been brought to another world with no instructions, no clear goals and no way home. It's a second chance to live a good life, but what will Cain be able to make of it?