Tensei Shitara Slime Datta Ken (WN) - Chapter 264

He holds a god-level sign-in system in his hand, punches the goose factory, and steps on the pig factory. Do you think there is no good game?
First feed you two mouthfuls of tainted milk powder, and then send you the legend of the dragon and the Hearthstone gold cartoon for free.
What? Still not satisfied? League of Kings out-of-print skin, give away!
Satisfied? Tch, this is just the beginning…

- Description from novelbuddy

No one knows when the first Clough door appeared. All people know is that a new era began when it was pushed open.Fortresses, sublimators, pillars of star essence, three-dimensional armaments, infinite energy, who can escape the sweeping tide of the times?In the abyss, the reverse realm, the skins, the alien gods, the mad king, the rulers, and the dark creatures, all howl in madness!Inside the black mist, the demons and ghosts crawl forward as a cross-dimensional migration silently brews.

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Qi Condensation. Foundation Establishment. Core Formation. In the current world, only these three realms are known to be achievable. Nascent Soul is but a legend and the realms above it lost to the the long river of time. The modern era is known as Cultivation Civilization, a balance of power and civility, excess and moderation. While cultivation remains a secret practice, it has long since exposed itself to the mundane world, quietly intertwined with each facet of society. While the world appears to be at peace, what lies underneath is a conflict between human, cultivator, and demon, brewing for ages and waiting to implode. Yet in the wake of humanity’s rapid industrialization, qi—and consequently cultivation—is dying.