I Was Banished from Heaven, Now I'm the Demon King's Stepdad?! - Chapter 28 – “Rin vs. Rin: Before the War Starts”

A recurring nightmare afflicted Khan's nights since the Second Impact. His dreams replayed the scenes of the crash of the Nak's spaceship, an alien race that the humans had defeated five hundred years ago.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

He reincarnated into a hunter world and became an underwater hunter.There were only 20 people in the entire country in this minor profession, but it didn’t matter. He liked the sea.“Crazy! There’s a real artifact?!”“Ahahaha!! How much is all this worth!!”But then, the Great Diving Era began.“Ah, it’s so beautiful… I want to see more, more…”“W-What is that!! Save me!!!”“Aaaargh!!! My head!! It feels like my head is going to explode!!”…It would be better not to go in there.

Upon waking up, Lu Qi turned into a tentacle monster.
As a tentacle monster, Lu Qi was not satisfied with using the tentacles to stun the elves, horsewoman, and magical girls. He wanted to learn the evil gods and make some big news in the multiverse.

“The abyss race never adapts to the environment, anyway, the environment will adapt to us sooner or later, and the same is true of Azeroth.”
“Humans, don’t play the tech tree anymore, you should add your points to” Spirit Vision “and” Mad Men’s Knowledge ”

“The inclusion of Godzilla, Quitola, Mozilla, and Ultraman in the” Luxury Lunch of the King’s Plan “is a matter of very little moral quality. Everyone has a responsibility to care for rare species.”
“Now take the initiative to blast your own worldview, we will give you a Saya sauce for free”

“Don’t worry about losing the SAN value, you can add a crazy attribute to be negative.”
“I decided to learn from the predecessors first and set myself a small goal, such as conquering the 6 billion carbon-based monkeys on this planet …”

- Description from Uukanshu